Review of the genus Cheilosia Meigen, 1822 (Diptera: Syrphidae) from the Caucasus, with the description of 14 new species

1 European Journal of Taxonomy 1023: 1–181 https://doi.org/10.5852/ejt.2025.1023.3097 europeanjournaloftaxonomy.eu ISSN 2118-9773 2025 · Bot S. et al. This work is licensed under a Creative Commons Attribution License (CC BY 4.0) Received: 23 November 2024 • Accepted: 4 July 2025 • Published: 21 October 2025 Topic editor: Tony Robillard • Section editor: Torbjørn Ekrem • Desk editor: Pepe Fernández Monograph urn:lsid:zoobank.org:pub:70585BDD-5981-4967-A09C-543CE5D7C717 Review of the genus Cheilosia Meigen, 1822 (Diptera: Syrphidae) from the Caucasus, with the description of 14 new species Sander BOT 1,* , Ximo MENGUAL 2 , Frank Van de MEUTTER 3 & Jeffrey H. SKEVINGTON 4   1 Gasterenseweg 1, 9467 TA Anloo, the Netherlands. 2 Museum Koenig Bonn, Leibniz-Institut zur Analyse des Biodiversitätswandels, Adenauerallee 127, 53113 Bonn, Germany. 3 Achterheide 16, 3980 Tessenderlo, Belgium. 4 146 Monty Drive, Ottawa, ON, K0A 3M0, Canada. * Corresponding author: [email protected] 2 Email: [email protected] 3 Email: Frank.V[email protected] 4 Email: [email protected] Abstract.AchecklistandanidentificationkeytothespeciesofthehoverflygenusCheilosia (Diptera: Syrphidae:Rhingiini)fromtheCaucasusRegionispresented,basedonliteratureresearchandnewfield expeditions.Thefieldexpeditionsandbarcodinganalysisresultedin14speciesnewtoscience:Cheilosia (Cheilosia) aurantia sp. nov., C. (C.) borjomi sp. nov., C. (C.) caucasi sp. nov., C. (C.) confusa sp. nov., C. (C.) gemmula sp. nov., C. (C) inarmata sp. nov., C. (C.) megaclama sp. nov., C. (C.) pogonias sp. nov., C. (C.) ushguliensis sp. nov., C. (C.) vansteenisi sp. nov., C. (Montanocheila) contrasta sp. nov., C. (M.) rufa sp. nov., C. (Taeniochilosia) ouwehandae Bot sp. nov. and C. (T.) longifacies sp. nov. Further, Cheilosia circassica Ståhls & Barkalov, 2017 syn. nov. is herewith considered junior synonym of Cheilosia armeniaca Stackelberg, 1960, and we recognize Cheilosia aenigmatosa Barkalov, 1993 stat. rev. as a distinct species and not a junior synonym of Cheilosia pollinifacies Stackelberg, 1968. After our survey, we consider Cheilosia caucasogenita Kuznetzov, 1997 to be a doubtful species. Our extensive genetic analysis based on DNA barcodes including other European Cheilosia taxa clusters all members of the subgenus Taeniochilosia Oldenberg, 1916 in a well-supported group. A short discussion on the Cheilosia fauna of the Caucasus Region is provided, detailing the presence of the different subgenera andthehighintraspecificmorphologicalvariabilitywithinCheilosia in the Caucasus. Keywords.Hoverflies,flowerflies,DNAbarcoding,Georgia,Armenia,newspecies,checklist, identificationkey,newrecord,newsynonym. Bot S., Mengual X., Van de Meutter F. & Skevington J.H. 2025. Review of the genus Cheilosia Meigen, 1822 (Diptera: Syrphidae) from the Caucasus, with the description of 14 new species. European Journal of Taxonomy 1023: 1–181. https://doi.org/10.5852/ejt.2025.1023.3097 European Journal of Taxonomy 1023: 1–181 (2025) 2 Introduction SyrphidaeLatreille,1802,commonlyknownashoverorflowerflies,isaspeciesrichfamilywithover 6200 described species (Marshall 2012; Evenhuis & Pape 2023). One of the largest genera in Syrphidae is Cheilosia Meigen, 1822 (member of Rhingiini) with some 450 described species (Evenhuis & Pape 2023; S. Bot unpubl. data). Species of Cheilosia are usually easy to distinguish from other genera by the general black ground-colour and the presence of well-developed parafaciae and a facial tubercle (Bot & Van de Meutter 2019, 2023; Skevington et al. 2019; Speight 2020b). Cheilosia is one of the few hoverflygenerawithvariouslarvalfeedingmodes:mostknownlarvaearephytophagous,butsomeare fungivorous or sap-feeders on trees (Rotheray 1993; Stuke 2000). The greatest number of species occurs in the Palaearctic Region (343 species); the remainder in the Nearctic (75) and Oriental regions (31), a few species (3) extend into the northern Neotropics while it is absent from Afrotropics (Peck 1988; Ståhls et al. 2004; Thompson et al. 2010). The Caucasus region lies between the Black Sea and the Caspian Sea and comprises the Republics of Armenia, Azerbaijan and Georgia (sometimes all together called Transcaucasia), parts of northeastern Turkey, northern Iran, and Russian republics and krais between the Sea of Azov and the Black Sea on the west and the Caspian Sea on the east (area known as Ciscaucasia or Northern Caucasus). The region is home to the Caucasus Mountains and is one of the global ‘biodiversity hotspots’ (Myers et al. 2000; Mittermeier et al. 2004). Previous research on Cheilosia in the Caucasus by mainly Russian authors was summarized by Barkalov (1993). After Barkalov (1993), few publications have covered Caucasian species of Cheilosia, with the most important ones being the revision of the subgenus Taeniochilosia Oldenberg,1916(Barkalov&Ståhls1997),thehoverflychecklistsofRussia(Barkalov&Mutin2018) and Georgia (Mengual et al. 2020), and Speight (2020a), who focuses on European species of Syrphidae but includes mentions to the Caucasus Region. Here, we present a new checklist of the CheilosiaoftheCaucasusincludinganidentificationkeyandthe description of 14 species new to science. The present study is framed in the Caucasus Barcode of Life project (CaBOL) (Thormann et al. 2019; Mengual et al. 2020). Material and methods For compiling the checklist of the Cheilosia of the Caucasus, we used literature records and our own datafromfieldwork.Ourliteratureresearchwasmainlybasedonthemostimportantworkscovering the Caucasus including Peck (1988), Barkalov (1993), Barkalov & Ståhls (1997), Gujabidze (2002), Barkalov & Mutin (2018), Mengual et al. (2020) and Speight (2020a). Most of the previous research in the region is already summarized in these publications. For each species, we cite only the references reporting the species for the Caucasus Region after an ‘en dash’ (–). We provide the page of the original publication when the references use the correct species concept as described by the original author. Although C. Claußen did not consistently use the same graphics for his surname in publications, we write his surname as Claussen for all his references used in this work. Field expeditions took place between 15 June and 27 July 2018, 8 and 22 June 2019 and 26 June and 20 July 2021 in Georgia, between 4 and 15 September 2021 and 14 and 24 May 2022 in Armenia, and between 25 May and 1 June 2022 and 30 April and 13 May 2023 in Georgia. Additionally, we studied material collected by Andrey A. Przhiboro in the Republic of North Ossetia-Alania between 30 May and 8 June 2018, which is temporarily housed at the Museum Koenig Bonn, and the material of Jonas Mortelmans collected in Georgia between 2 and 12 September 2019 (housed in the personal collection of Frank Van de Meutter). During the expeditions, several Armenian and Georgian provinces were visited and the specimens were collected using an entomological hand net, unless stated otherwise. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 3 Most results of the 2018 expedition are already reported in Mengual et al. (2020) and are not repeated here. If a species has no recent records in Mengual et al. (2020) but is recorded from 2019, 2021, 2022 and/or 2023, details are reported here. If a species has recent detailed records in Mengual et al. (2020) and the species is recorded again from 2019, 2021, 2022 and/or 2023, details of the 2019, 2021 2022 and/or2023recordsarenotgivenhere,withtheexceptioniftherecordsrepresentthefirstreportfora country. We list the species of Cheilosia in the Results following the alphabetic order of the species epithet, not consideringthesubgenus,tofacilitateinformationfinding. Morphological terminology follows van Steenis et al. (2023), in addition to those terms related to male genitaliathatfollowBarkalov&Ståhls(1997)andClaussen(1998).Thesubgenericclassificationof CheilosiafollowsBarkalov(2002).ForidentificationwemainlyusedkeyspublishedinViolovitsh (1983), Barkalov (1993), Barkalov & Ståhls (1997), Claussen (1998), Bartsch et al.(2009),Vujićet al. (2013), Barkalov & Ståhls (2017), Speight & Sarthou (2017) and Bot & Van de Meutter (2023). Digital images and line drawings All photographs were taken with a Canon EOS 6D camera with a Mejiro Genossen FL0530 4.0/110 Float Lens (habitus photographs) or Leitz-Wetzlar Photar 1:2/25 macro lens (other photographs). Before stacking in Helicon Focus ver. 7.7.5 (Kharkiv, Ukraine), exposure and sharpening of the photos was adjusted in Adobe® Lightroom Classic (ver. 10.4). For line drawings of the genitalia, the genitalia were cleared and photographed with the camera of a mobile phone through a binocular microscope. The photowasredrawnwithafinelinerontracingpaperfromthemonitor.Bodylengthwasmeasuredfrom the anterior oral margin to the posterior end of the abdomen, in lateral view. Wing length was measured from the wing tip to the basicosta. Institutional abbreviations The following acronyms are used to indicate entomological collections. ASW = private collection of Axel Ssymank, Wachtberg, Germany CNC = Canadian National Collection of Insects, Arachnids, and Nematodes, Ottawa, Ontario, Canada FMT = private collection of Frank Van de Meutter, Tessenderlo, Belgium GPA = private collection of Gerard Pennards, Amersfoort, the Netherlands JMG = private collection of Jonas Mortelmans, Gent, Belgium JSB = private collection of Jeroen van Steenis, Baarn, the Netherlands LHH = private collection of Lenze Hofstee, Haren, the Netherlands MTD = Senckenberg Naturhistorische Sammlungen Dresden, Museum für Tierkunde, Dresden, Germany NBC = Naturalis Biodiversity Center (former Rijksmuseum van Natuurlijke Historie, RMNH), Leiden, the Netherlands SBA = private collection of Sander Bot, Anloo, the Netherlands WOR = private collection of Wout Opdekamp, Rochefort, Belgium XLS = private collection of Xavier Lair, Sournia, France ZISP = Zoological Institute of the Russian Academy of Sciences, St Petersburg, Russia ZFMK = Museum Koenig Bonn, Leibniz-Institut zur Analyse des Biodiversitätswandels, Bonn, Germany European Journal of Taxonomy 1023: 1–181 (2025) 4 Molecular work The nucleotide sequence of the mitochondrial Cytochrome c oxidase subunit I (COI) gene, also known as a DNA barcode (Hebert et al. 2003a, 2003b), was obtained from selected specimens. One or two legs of each sequenced specimen were used for DNA extraction. DNA primers, as well as extraction, amplification,purification,sequencingprotocolsandeditionwerecarriedoutasdescribedinRozoLopez & Mengual (2015) for specimens sequenced at ZFMK, or as described in Gibson et al. (2010) for specimens sequenced at CNC. The remnants of the studied specimens were preserved and properly labelled as DNA voucher specimens. All new sequences were submitted to GenBank via BOLD (www.boldsystems.org). GenBank accession numbers are listed for each sequenced specimen in the text or in the Supp.file2: Table S1. Public nucleotide sequences (with more than 500 bp and without contaminants) of the studied species of Cheilosia available at BOLD were downloaded (https://www.boldsystems.org/index.php; accessed on 19 January 2024). The public sequences and the newly obtained sequences were aligned without gaps or stop codons using Geneious Prime ver. 2022.1.1 (Biomatters Ltd). Specimen information (locality, date,collector,identifieranduniqueidentifier)isaccessibleviatheGenBankAccessionNumbers (Supp.file2: Table S1) and in BOLD (https://www.boldsystems.org/) under the data set DS-CHEICAUC (https://doi.org/10.5883/DS-CHEICAUC). A distance-based Neighbor-Joining (NJ) analysis was done using the Jukes-Cantor Model as implemented in the software Geneious Prime ver. 2022.1.1 (Supp.file1: Fig. S1). The DNA barcode of Rhingia campestris Meigen, 1822 (ZFMK-DIP-00077699|ZFMK-TIS-8009535) was constrained as the root for the NJ tree. Bootstrap support values (BS) were estimated from 1000 replicates directly from Geneious Prime ver. 2022.1.1. Uncorrected pairwise distances (p-distances) were calculated in Geneious Prime ver. 2022.1.1 and provided in the Supp.file3: Table S2. Results An overview of the species of Cheilosia occurring in the Caucasus region Class Insecta Linnaeus, 1758 Order Diptera Linnaeus, 1758 Family Syrphidae Latreille, 1802 Subfamily Eristalinae Newman, 1834 Genus Cheilosia Meigen, 1822 Cheilosia (Cheilosia) abagoensis Skufjin, 1979 Fig. 1 Cheilosia abagoensis Skufjin, 1979: 194. Cheilosia abagoensis – Peck 1988: 95. — Barkalov 1993: 721. — Barkalov & Mutin 2018: 482. — Mengual et al. 2020: 14. Differential diagnosis It can be confused with several other species of Cheilosia that have the combination of a pilose eye, bare face, shiny sterna, black legs and posterior margin of scutellum with setae (e.g., C. caucasi sp. nov., C. gemmula sp. nov., C. rhynchops).Nevertheless,itcanberelativelyeasyidentifiedbytheshiny posterior anepisternum, at least slightly pruinose in the others, and the blackish infuscate wings (Fig. 1A, C), hyaline or almost so in the other mentioned species. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 5 Material examined Collected in 2018, 2019 and 2021; see Mengual et al. (2020) for detailed records from 2018. Genetics DNA barcodes of C. abagoensis cluster all together with high support (BS = 99.6%), including three specimens of C. caucasi sp. nov. Biology During our expeditions, collected between June 15th and 13 July between 1900 and 2295 m a.s.l. All specimens were collected on alpine meadows. Distribution Caucasus (Russia, Georgia). Fig. 1. Cheilosia (Cheilosia) abagoensis Skufjin, 1979. Collected in Georgia. A.♂(SBA,SB.002704); habitus, lateral view; body length 9.2 mm. B.♂(SBA,SB.002704);head,lateralview;eyewidth 1.3 mm. C.♂(SBA,SB.002707);habitus,dorsalview;bodylength8.7mm.D.♀(SBA,SB.002702); head, lateral view; eye width 1.2 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 6 Cheilosia (Taeniochilosia) aenigmatosa Barkalov, 1993 stat. rev. Fig. 2 Cheilosia aenigmatosa Barkalov, 1993: 700. Cheilosia grisella Becker, 1894 – Stackelberg & Richter 1968: 246. — Peck 1988: 104. — Barkalov & Ståhls 1997: 28. — Gujabidze 2002: 245. — Mengual et al. 2020: 25. — Speight 2020a: 35. Cheilosia aenigmatosa – Barkalov 1993: 700. — Barkalov & Ståhls 1997: 52. — Barkalov & Mutin 2018: 486. Differential diagnosis Cheilosia aenigmatosaisidentified as belonging to the subgenus Taeniochilosia by the combination of bareeye,blacklegsandtheanteriorprocessoflunulanotbroadlyconfluentwiththeface(Barkalov& Ståhls1997).ThemalegenitaliaarefiguredinBarkalov(1993).ThemaleofC. aenigmatosa is very similar to C. pollinifacies and can be distinguished as follows: posterior margin of scutellum with few and thin setae, diameter almost as thin as scattered black pile on disc of scutellum (Fig. 2E) (in C. pollinifacies the posterior margin of scutellum has multiple setae with a diameter much larger than diameter of scattered long black pile on disc of scutellum; Fig. 56E), scutum with dense erect short golden pile, with sparse long black erect pile intermixed (in C. pollinifacies scutum also with sparse long black pile, but short pile on scutum semi-adpressed, variable in colour, ranging from predominantly black to predominantly golden). Females of C. aenigmatosa differ from C. pollinifacies by the absence of black setae or pile on posterior margin of scutellum, while black setae are present on posterior margin of scutellum in C. pollinifacies. Genetically, it is similar to C. ouwehandae Bot sp. nov., but the male differs in many ways (the female of C. ouwehandae remains unknown): C. aenigmatosa is larger (body size usually at least 8 mm instead of 6.5 mm), face and parafacia densely pruinose (slightly pruinose in C. ouwehandae), facial tubercle less well developed, not further projecting than mouth edge (rounder, and further protruding, well beyond mouth edge in C. ouwehandae), postpedicel black (basoventrally orange in C. ouwehandae), frontal triangle with large proportion of yellow pile (pile black in C. ouwehandae), pile on scutum golden instead of whitish, and posterior margin of scutellum with black pile setae instead of black setae and abdomen with less dense pruinosity. Material examined Collected in 2018, 2019 and 2021, but 2018 records were not published in Mengual et al. (2020). Thus, all records are reported here. GEORGIA – Adjara Region•1♀;KintrishiNatureReserve;41.7619°N,42.1162°E;2462ma.s.l.; 16Jun.–30Jun.2018;GGBC-membersleg;ZFMK,ZFMK-TIS-8010536•1♀;KintrishiNature Reserve;41.7619°N,42.1162°E;2462ma.s.l.;30Jun.–14Jul.2018;GGBC-membersleg;ZFMK, ZFMK-TIS-8010398•1♀;MtiralaN.P.;41.6535°N,41.8730°E;1106ma.s.l.;16Jul.2021;S.Bot leg.;BA, SB.003061. – Imereti•2♂♂;roadfromAbastumanitoSairme;41.824°N,42.847°E; 2150ma.s.l.;10Jun.2019;F.VandeMeutterleg.;FMT•1♂;Abastumaniarea,alongpath;41.823°N, 42.840°E;2025ma.s.l.;11Jun.2019;F.VandeMeutterleg.;FMT.–Mtskheta-Mtianeti•1♂; Gudauri-pass;42.5336°N,44.4751°E;2210ma.s.l.;11Jul.2019;A.Ssymankleg.;ASW,Ssy950401,ZFMK-TIS-8009412•1♀;samedataasforpreceding;ASW,Ssy9504-02,ZFMK-TIS-8009413. – Samegrelo-Zemo Svaneti•1♀;43.0319°N,42.8272°E;1905ma.s.l.;13Jun.2019;X.Mengual leg;ZFMK,ZFMK-DIP-00066299=ZFMK-TIS-8008764•1♂;42.900°N,42.934°E;2700ma.s.l.; 17Jun.2019;S.Botleg.;SBA,SB.003064•1♀;42.9140°N,43.0911°E;2575ma.s.l.;18Jun.2019; X.Mengualleg.;ZFMK,ZFMK-DIP-00066298=ZFMK-TIS-8006837•1♂;7kmWofUshguli,near hilltop;42.906°N,42.937°E;2615ma.s.l.;16Jun.2019;F.VandeMeutterleg.;FMT•1♀;7.5km NofMestia,pathtoglacier;42.738°N,43.113°E;1800ma.s.l.;14Jun.2019;F.VandeMeutterleg.; FMT•3♂♂;43.0275°N,42.9115°E;2887ma.s.l.;14Jul.2021;S.Botleg.;SBA,SB.003058to BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 7 SB.003060•2♀♀;samedataasforpreceding;SBA,SB.003056,SB.003057.–Samtskhe-Javakheti •1♂;BorjomiN.P.;41.824°N,42.848°E;2165ma.s.l.;10Jun.2019;S.Botleg.;SBA,SB.003062• 1♀;samedataasforpreceding;SBA,SB.003063. RUSSIA – Kabardino-Balkaria•1♀;43.4841°N,43.1006°E;1776ma.s.l.;6Jun.2018;A.Przhiboro leg.; ZFMK, ZFMK-DIP-00078649 = ZFMK-TIS-8009592 • 2 ♂♂; 43.4795° N, 43.0971° E; 1836 m a.s.l.; 7–8 Jun. 2018; A. Przhiboro leg.; yellow plates; ZFMK, ZFMK-DIP-00078658 = ZFMKTIS-8009602,ZFMK-DIP-00078660=ZFMK-TIS-8009567•2♀♀;samedataasforpreceding;ZFMK, ZFMK-DIP-00078653 = ZFMK-TIS-8009596; ZFMK-DIP-00078659 = ZFMK-TIS-8009566; ZFMK. Genetics DNA barcodes of C. aenigmatosa were resolved into three clusters with high support (BS = 96.7–100%). DNA barcodes of European specimens of C. grisella were grouped together with high support (BS = 98.7%). See Remarks. Fig. 2. Cheilosia (Taeniochilosia) aenigmatosa Barkalov, 1993. Collected in Georgia. A.♂(SBA, SB.003064); habitus, lateral view; body length 8.3 mm. B.♂(SBA,SB.003064);habitus,dorsalview; body length 8.3 mm. C.♂(SBA,SB.003064);head,lateralview;eyewidth1.1mm.D.♀(SBA, SB.003063); head, lateral view; eye width 1.3 mm. E.♂(SBA,SB.003062);scutellum,posteriorview; scutellum width 1.7 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 8 Remarks Previous records of C. grisella from the Caucasus are referred here to as C. aenigmatosa and C. grisella is considered absent from the Caucasus Region. Barkalov & Ståhls (1997) synonymized C. aenigmatosa with C. pollinifacies without providing an explanation or comment. Our genetic study resolved C. pollinifacies and related species in several clusters. One group corresponds to the original description of C. pollinifacies and three other groups match the description of C. aenigmatosa, with C. ouwehandae sp. nov. branching in between (Supp.file1: Fig. S1). Although genetically similar, C. ouwehandae differs from C. aenigmatosa morphologically (see Differential diagnosis). Within C. aenigmatosa,wecouldnotfindmorphological differences between the genetic clusters. Here we reinstate C. aenigmatosa as a genetically and morphologically different species from C. pollinifacies. Biology During our expeditions, collected between 6 June and 16 July at an altitude between 1106 and 2887ma.s.l.BehaviourdifficulttoascertainduetoconfusionwiththeverysimilarC. pollinifacies with which it often co-occurs. At places where C. aenigmatosa was caught, individuals belonging to C. aenigmatosa or C. pollinifacies were often found in clearings in forest, along forest edges or near tall vegetationinalpinemeadows,visitinglowflowersincludingCaltha palustris L. and Ranunculus sp. Distribution Caucasus (Russia, Georgia). Cheilosia (Cheilosia) aerea Dufour, 1848 Fig. 3 Cheilosia aerea Dufour, 1848: 209. Chilosia correcta Becker, 1894: 488. Syn. by Claussen & Thompson (1996). Chilosia zetterstedti Becker, 1894: 430. Syn. by Claussen & Thompson (1996). Chilosia zetterstedti – Stackelberg & Richter 1968: 250. — Stackelberg 1970: 62. — Peck 1988: 121. Chilosia correcta – Barkalov 1993: 724. Cheilosia zetterstendti Becker, 1921 [sic] – Gujabidze 2002: 246. Cheilosia aerea – Barkalov & Mutin 2018: 482. — Mengual et al. 2020: 14. — Speight 2020a: 26. Differential diagnosis Very similar to the species of the proxima group, and therefore often overlooked. It shares the following characters with the proxima group: eye pilose, face bare, legs bicoloured, posterior margin of scutellum with setae and sterna pilose. However, in C. aerea the posterodorsal corner of the anterior anepisternum is pilose, bare in all species of the proxima group, and the sterna are less pruinose in some specimens and populations. Morphologically and genetically, it is close to C. vansteenisi sp. nov., but that species has the posterodorsal corner of the anterior anepisternum bare. Moreover, C. aerea has the scutum more coarsely punctured, terga more pruinose and terga with on average more black pile. For more differences with C. vansteenisi, see the Differential diagnosis of that species. Material examined Not collected in 2018, but collected in 2019 and 2022. ARMENIA – Ararat Province•5♂♂;surroundingsofGeghardMonastery;40.13859°N,44.81728°E; 1720 m a.s.l.; 22 May 2022; X. Mengual leg.; ZFMK, ZFMK-DIP-00093544 = ZFMK-TIS-8014619, BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 9 ZFMK-DIP-00093545, ZFMK-DIP-00093550, ZFMK-DIP-00093551 = ZFMK-TIS-8014627, ZFMKDIP-00094506•1♀;samedataasforpreceding;ZFMK,ZFMK-DIP-00093556.–Syunik Province •1♀;fromLichktotheZvaravankMonastery;39.05497°N,46.171353°E;1765ma.s.l.;16May 2022;X.Mengualleg.;ZFMK,ZFMK-DIP-00093041=ZFMK-TIS-8014612•6♂♂;nearGorayk, SpandarianReservoir;39.684513°N,45.777478°E;2078ma.s.l.;19May2022;X.Mengualleg.; ZFMK, ZFMK-DIP-00093263 = ZFMK-TIS-8014620, ZFMK-DIP-00093265, ZFMK-DIP-00093269 = ZFMK-TIS-8014625, ZFMK-DIP-00093270, ZFMK-DIP-00093271, ZFMK-DIP-00093273 • 3♀♀;samedataasforpreceding;ZFMK,ZFMK-DIP-00093277,ZFMK-DIP-00093278,ZFMKDIP-00093280. Fig. 3. Cheilosia (Cheilosia) aerea Dufour, 1848. Collected in Armenia. A.♂(ZFMK,ZFMKTIS-8014627); habitus, lateral view; body length 8.9 mm. B.♂(ZFMK,ZFMK-TIS-8014627);head, lateral view; eye width 1.4 mm. C.♂(ZFMK,ZFMK-TIS-8014627);habitus,dorsalview;bodylength 8.9 mm. D.♀(ZFMK);head,lateralview;eyewidth1.3mm.Nottoscale. European Journal of Taxonomy 1023: 1–181 (2025) 16 called the albagroup;foradiagnosisoftheEuropeanspecies,seeVujić&Claussen(2000).Inthe Caucasus, this species may only be confused with C. megaclama sp. nov. but C. atypica has the tibiae with indistinct black ring (tibiae with distinct black ring in the middle in C. megaclama) and the tarsi are dorsally predominantly yellow instead of predominantly black as in C. megaclama. Material examined Species not collected. Distribution The only known specimen was collected on the summit of Belaya Mt, Russia, Northern Caucasus. Cheilosia (Cheilosia) aurantia sp. nov. urn:lsid:zoobank.org:act:7BF1EF77-0437-4956-9530-8792EA566192 Figs 8–9 Chilosia omissa Becker, 1894: 466. Syn. with Cheilosia lenis by Claussen & Speight (2007). Chilosia omissa – Stackelberg & Richter 1968: 247. — Peck 1988: 112. — Barkalov 1993: 718. — Barkalov & Mutin 2018: 483. Chilosia lenis Becker – Mengual et al. 2020: 18. Fig. 7. Cheilosia (Cheilosia) atypicaBarkalov,1993.Holotype,♀(ZISP);habitus,dorsalview.Photo by Vladimir Neimorovets (http://www.zin.ru/collections). BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 17 Differential diagnosis Cheilosia aurantia sp. nov. is very similar to C. lenis Becker, 1894, sharing slightly elongated face, very long mainly black pile on eye, (partly) yellow legs, setae on posterior margin of scutellum absent or of reduced width, dorsal and ventral pile patches on katepisternum joined and sterna shiny. The male of C. aurantia is similar to that of C. lenis but: with a swollen frons (not swollen in C. lenis), scutum, scutellum and pleura with more extensive black pile (almost exclusively with yellow pile in C. lenis), protibia with a black marking on the posterior side only (with a continuously black mark, covering anterior and posterior part, in C. lenis), abdomen completely covered with long erect pile, also medially (C. lenishaveshorterpilemediallyonthetergaandmoreadpressed),andamuchmoreextensivefieldof microtrichia on surstylus in C. aurantia (Fig. 9D) compared with the male genitalia of C. lenis. Females of C. aurantia are like those of C. lenis but easily distinguished by the entirely orange femora and tibiae (Fig. 8C) (in C. lenis females the femora are black except orange apex and the tibiae have a broad black ring medially) and the face is slightly more protruding downwards (Fig. 9B). Etymology The species name is derived from the Latin ‘aurantium’ meaning ‘orange’ (Brown 1956: 112), and it refers to the almost entirely orange legs of the female. Species epithet is to be treated as an adjective. Material examined Holotype GEORGIA•♂;Samegrelo-ZemoSvaneti,nearUshguli,uptotheruins;42.910°N,43.007°E; 2295 m a.s.l.; 17 Jun. 2019; X. Mengual leg.; ZFMK, ZFMK-TIS-8008829 = ZFMK-DIP-00066574. Paratypes ARMENIA – Lori •2♂♂,2♀♀;30Apr.2011;T.Zeegersleg.;GPA. GEORGIA – Adjara•1♀;KintrishiNatureReserve;41.7433°N,42.0840°E;1235ma.s.l.;1–15Jun. 2018;GGBC-membersleg.;Malaisetrap,storedinalcohol;ZFMK,ZFMK-TIS-8010514•1♀;Kintrishi NatureReserve;41.75517°N,42.11249°E;2268ma.s.l.;2–16Jun.2018;GGBC-membersleg.;Malaise trap, stored in alcohol; ZFMK, ZFMK-TIS-8010567. – Kakheti•1♀;LagodekhiN.P.;41.8524°N, 46.2877°E;665ma.s.l.;12–23Apr.2014;G.Japoshvilileg.;Malaisetrap;CNC,CNC1449289•4♂♂; LagodekhiN.P.;41.8767°N,46.2429°E;615ma.s.l.;2May2023;S.Botleg.;SBA,SB.003024to SB.003027•5♂♂,2♀♀;LagodekhiN.P.;41.8777°N,46.2436°E;625ma.s.l.;2May2023;F.Van deMeutterleg.;FMT•2♂♂;LagodekhiN.P.;41.8747°N,46.2415°E;600ma.s.l.;2May2023; W. Opdekamp leg.; WOR, E013, E021. – Mtskheta-Mtianeti•3♀♀;TbilisiN.P.;41.880°N,45.023°E; 1289ma.s.l.;4May2023;S.Botleg.;SBA,SB.003028toSB.003030•5♂♂,3♀♀;TbilisiN.P.; 41.877°N,45.0138°E;1250ma.s.l.;4May2023;F.VandeMeutterleg.;FMT•3♀♀;TbilisiN.P.; 41.8802°N,45.0220°E;1279ma.s.l.;4May2023;W.Opdekampleg.;WOR,A020,A034,A036• 5♂♂;Lutkhubi;42.3797°N,44.7969°E;1463ma.s.l.;6May2023;S.Botleg.;SBA,SB.003031to SB.003035•6♀♀;samedataasforpreceding;SBA,SB.003036toSB.003041•1♂;samedataasfor preceding;L.Hofsteeleg.;LHH•2♂♂,4♀♀;Lutkhubi;42.3867°N,44.79°E;1580ma.s.l.;6May 2023;F.VandeMeutterleg.;FMT•3♀♀;Lutkhubi;42.3930°N,44.7929°E;1700ma.s.l.;6May 2023;W.Opdekampleg.;WOR,A001,A015,A017•1♀;Lutkhubi;42.3936°N,44.7923°E; 1760ma.s.l.;8May2023;F.VandeMeutterleg.;FMT•1♂;Tsinamkhari;42.3914°N,44.7562°E; 1200ma.s.l.;8May2023;W.Opdekampleg.;WOR,B001•1♀;samedataasforpreceding;WOR, B010•1♂;Kithoki;42.4147°N,44.7548°E;1240ma.s.l.;8May2023;W.Opdekampleg.;WOR, A012•2♀♀;samedataasforpreceding;WOR,A003,A014•2♂♂;Lutkhubi;42.3930°N,44.7929°E; 1734 m a.s.l.; 8 May 2023; W. Opdekamp leg.; WOR, C007, C033. – Racha-Lechkhumi and Kvemo Svaneti•1♂;Tsana;42.909°N,43.142°E;1900ma.s.l.;29Jun.2018;S.Botleg.;SBA,SB.002992 European Journal of Taxonomy 1023: 1–181 (2025) 18 •3♀♀;samedataasforpreceding;SBA,SB.002993toSB.002995•2♂♂;Zeskho;42.888°N, 43.233°E;1900ma.s.l.;30Jun.2018,S.Botleg.;SBA,SB.002996,SB.002997•1♀;samedataasfor preceding;SBA,SB.002998•2♀♀;Zeskho;42.888°N,43.233°E;1900ma.s.l.;1Jul.2018;S.Bot leg.;SBA,SB.002999,SB.003000•1♀;Zeskho;42.888°N,43.233°E;1900ma.s.l.;2Jul.2018; S.Botleg.;SBA,SB.003001•3♀♀;Tsana;42.913°N,43.142°E;1951ma.s.l.;18Jun.2019; L.Hofsteeleg.;LHH•2♂♂;Tsana;42.90°N,43.14°E;1830ma.s.l.;18Jun.2019;J.vanSteenisleg.; JSB,2019-00.897=ZFMK-TIS-8009604,2019-01.016•4♀♀;samedataasforpreceding;JSB,201901.017–2019-01.020•1♂;nearTsana;42.9011°N,43.1422°E;1835ma.s.l.;18Jun.2019;X.Mengual leg.;ZFMK,ZFMK-DIP-00066571•1♀;samedataasforpreceding;ZHMK,ZFMK-DIP-00066546• 1♂;Tsana;42.888°N,43.143°E;1760ma.s.l.;18Jun.2019;X.Mengualleg.;ZFMK,ZFMKDIP-00066565•1♀;samedataasforpreceding;ZFMK,ZFMK-DIP-00066536•2♂♂;Tsana; 42.915°N,43.143°E;1969ma.s.l.;19Jun.2019;L.Hofsteeleg.;LHH•1♂,1♀;Tsana;42.9089°N, 43.1425°E;1900ma.s.l.;19Jun.2019;F.VandeMeutterleg.;FMT•1♂;Tsana;42.916°N,43.142°E; 1975ma.s.l.;19Jun.2019;X.Mengualleg.;ZFMK,ZFMK-DIP-00066564•2♀♀;samedataasfor preceding; ZFMK, ZFMK-DIP-00066534, ZFMK-DIP-00066535. – Samegrelo-Zemo Svaneti•2♂♂; Mestia;43.080°N,42.762°E;1800ma.s.l.;22Jun.2018;S.Botleg.;SBA,SB.003004,SB.003005• 2♀♀;samedataasforpreceding;SBA,SB.002985,SB.002986•1♀;samedataasforpreceding;XLS, SB.002987•1♂;Ushguli;42.914°N,43.010°E;2100ma.s.l.;23Jun.2018;S.Botleg.;SBA, SB.002988•1♂;42.955°N,42.968°E;2130ma.s.l.;26Jun.2018;S.Botleg.;SBA,SB.002990•1♀; samedataasforpreceding;SBA,SB.002989•1♀;42.912°N,42.937°E;2430ma.s.l.;27Jun.2018; S.Botleg.;SBA,SB.002991•2♂♂;Mestia;43.02°N,42.89°E;2600ma.s.l.;13Jun.2019;J.van Steenisleg.;JSB,2019-00.896,2019-01.003•1♂;nearMestia;43.0254°N,42.8906°E;2550ma.s.l.; X.Mengualleg.;ZFMK,ZFMK-DIP-00066576=ZFMK-TIS-8008830•2♀♀;samedataasfor preceding;ZFMK,ZFMK-DIP-00066530,ZFMK-DIP-00066549•2♂♂,2♀♀;Mestia;2550ma.s.l.; 43.0256°N,42.8908°E;13Jun.2019;F.VandeMeutterleg.;FMT•1♂;EofMestia;43.02°N, 42.87°E;2350ma.s.l.;13Jun.2019;J.vanSteenisleg.;JSB,2019-01.004•1♀;samedataasfor preceding;JSB,2019-01.005•1♀;43.0259°N,42.9103°E;2863ma.s.l.;13Jun.2019;J.H.Skevington leg.;CNC,CNC1386373•2♂♂;EofMestia;43.0283°N,42.8787°E;2345ma.s.l.;13Jun.2019; X.Mengualleg.;ZFMK,ZFMK-DIP-00066569,ZFMK-DIP-00066570•1♀;samedataasfor preceding;ZFMK,ZFMK-DIP-00066544•1♂;Mestia;7.5kmNofMestia,43.1178°N,42.7253°E; 1875ma.s.l.;14Jun.2019;F.VandeMeutterleg.;FMT•2♀♀;Mestia,43,1166°N,42,7276°E; 1850 m a.s.l.; 14 Jun. 2019; X. Mengual leg.; ZFMK, ZFMK-DIP-00066542, ZFMK-DIP-00066543 = ZFMK-TIS-8008826•1♂;43.1118°N,42.7437°E;1697ma.s.l.;14Jun.2019;J.H.Skevingtonleg.; CNC,CNC1386473•1♂,1♀;Ushguli;42.948°N,43.070°E;2258ma.s.l.;15Jun.2019;L.Hofstee leg.;LHH•2♀♀;Ushguli;42.56°N,43.04°E;2260ma.s.l.;15Jun.2019;J.vanSteenisleg.;JSB, 2019-01.006,2019-01.007•2♂♂;Ushguli;42.9500°N,43.0719°E;2270ma.s.l.;15Jun.2019;F.Van deMeutterleg.;FMT•2♀♀;Ushguli;42.91°N,43.01°E;2100ma.s.l.;15Jun.2019;J.vanSteenis leg.;JSB,2019-01.008,2019-01.009•1♀;Ushguli;42.909°N,43.007°E;2294ma.s.l.;16Jun.2019; S.Botleg.;SBA,SB.003017•1♂,1♀;42.900°N,42.934°E;2700ma.s.l.;16Jun.2019;L.Hofstee leg.;LHH•1♀;Ushguli;42.9149°N,43.0029°E;2081ma.s.l.;16Jun.2019;J.H.Skevingtonleg.; CNC,CNC1386643•1♂;Ushguli;42.9370°N,42.9061°E;2615ma.s.l.;16Jun.2019;F.Vande Meutterleg.;FMT•1♂;Ushguli;42.91°N,43.00°E;2070ma.s.l.;16Jun.2019;J.vanSteenisleg.; JSB,2019-01.010•1♀;samedataasforpreceding;JSB,2019-01.011•1♂;Ushguli;42.906°N, 42.937°E;2615ma.s.l.;16Jun.2019;X.Mengualleg.;ZFMK,ZFMK-DIP-00066575•1♀;samedata asforpreceding;ZFMK,ZFMK-DIP-00066547•1♂,1♀;Ushguli;42.910°N,43.000°E;2120ma.s.l.; 17Jun.2019;L.Hofsteeleg.;LHH•1♂;Ushguli;2kmSWofUshguli;42.8986°N,43.0052°E; 2550ma.s.l.;17Jun.2019;F.VandeMeutterleg.;FMT•1♂;Ushguli;42.90°N,42.93°E; 2600ma.s.l.;17Jun.2019;J.vanSteenisleg.;JSB,2019-01.012•2♂♂;Ushguli;42.91°N,42.93°E; 2290ma.s.l.;17Jun.2019;J.vanSteenisleg.;JSB,2019-01.013,2019-01.014•4♂♂;Ushguli; 42.910°N,43.007°E;2295ma.s.l.;17Jun.2019;X.Mengualleg.;ZFMK,ZFMK-DIP-00066568, BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 19 ZFMK-DIP-00066572,ZFMK-DIP-00066573,ZFMK-DIP-00066574=ZFMK-TIS-8008829•1♀; samedataasforpreceding;ZFMK,ZFMK-DIP-00066545•3♂♂;Ushguli;42.898°N,43.008°E; 2601ma.s.l.;18Jun.2019;S.Botleg.;SBA,SB.003018toSB.003020•2♂♂,1♀;Ushguli; 42.9370°N,42.9061°E;2550ma.s.l.;18Jun.2019;F.VandeMeutterleg.;FMT•2♂♂;Ushguli; 42.8964°N,43.0047°E;2565ma.s.l.;18Jun.2019;J.H.Skevingtonleg.;CNC,CNC1386811, CNC1386813•1♀;samedataasforpreceding;CNC,CNC1386810•1♂;Ushguli;42.91°N,43.09°E; 2585ma.s.l.;18Jun.2019;J.vanSteenisleg.;JSB,2019-01.015•1♂;Tsana;42.88°N,43.15°E; 1900ma.s.l.;19Jun.2019;J.vanSteenisleg.;JSB,2019-01.021•1♂;42.820°N,43.159°E; 1439ma.s.l.;20Jun.2019;L.Hofsteeleg.;LHH•1♀;nearShovi;42.713°N,43.701°E;2022ma.s.l.; 7Jul.2021;S.Botleg.;SBA,SB.003021•1♂;nearShovi;42.665°N,43.656°E;2203ma.s.l.;10Jul. 2021;S.Botleg.;SBA,SB.003022•1♀;samedataasforpreceding;SBA,SB.003023.–SamtskheJavakheti•2♂♂;BorjomiN.P.;41.857°N,43.208°E;1900ma.s.l.;18Jun.2018;S.Botleg.;SBA, SB.002978,SB.002979•6♀♀;BorjomiN.P.;41.867°N,43.251°E;2000ma.s.l.;18Jun.2018;S.Bot leg.;SBA,SB.002972toSB.002977•1♂;BorjomiN.P.;41.810°N,43.119°E;2050 m a.s.l.; 19 Jun. 2018;S.Botleg.;XLS,SB.002983•3♀♀;BorjomiN.P.;41.846°N,43.145°E;1800ma.s.l.;19Jun. 2018;S.Botleg.;SBA,SB.002980toSB.002982•1♂;BorjomiN.P.;41.777°N,43.139°E; 1720ma.s.l.;20Jun.2018;S.Botleg.;SBA,SB.002984•1♂;roadfromSakiretoTsikhisjvari; 41.728°N,43.364°E;2327ma.s.l.;9Jun.2019;S.Botleg.;SBA,SB.003008•4♀♀;samedataasfor preceding;SBA,SB.003002,SB.003003,SB.003006=CNCdatabasingS.Bot924,SB.003007•2♂♂, 4♀♀;samedataasforpreceding;L.Hofsteeleg.;LHH•3♂♂,6♀♀;samedataasforpreceding; F.VandeMeutterleg.;FMT•5♂♂;roadfromSakiretoTsikhisjvari;41.7299°N,43.3684°E; 2245 m a.s.l.; 9 Jun. 2019; J.H. Skevington leg.; CNC, CNC1385954, CNC1385976, CNC1385997, CNC1386001,CNC1386039•5♀♀;samedataasforpreceding;CNC,CNC1385938,CNC1385984, CNC1386009,CNC1386025,CNC1386037•6♂♂;roadfromSakiretoTsikhisjvari;41.72°N, 43.36°E;2250ma.s.l.;9Jun.2019;J.vanSteenisleg.;JSB,2019-00.890to2019-00.892,2019-00.980 to2019-00.982•5♀♀;samedataasforpreceding;JSB,2019-00.983to2019-00.987•6♂♂;roadfrom SakiretoTsikhisjvari;41.7251°N,43.3605°E;2519ma.s.l.;9Jun.2019;X.Mengualleg.;ZFMK, ZFMK-DIP-00066553, ZFMK-DIP-00066554, ZFMK-DIP-00066555 = ZFMK-TIS-8008828, ZFMKDIP-00066556 to ZFMK-DIP-00066558 • 6 ♀♀; same data as for preceding; ZFMK, ZFMKDIP-00066525toZFMK-DIP-00066529,ZFMK-DIP-00066548•1♀;roadfromSakiretoTsikhisjvari; 41.7304°N,43.3342°E;1900ma.s.l.;9Jun.2019;X.Mengualleg.;ZFMK,ZFMK-DIP-00066524• 6♂♂;BorjomiN.P.;41.824°N,42.848°E;2165ma.s.l.;10Jun.2019;S.Botleg.;SBA,SB.003009 toSB.003014•1♀;samedataasforpreceding;SBA,SB.003015•5♂♂,2♀♀;samedataasfor preceding;L.Hofsteeleg.;LHH•2♂♂;BorjomiN.P.;41.83°N,42.81°E;2260ma.s.l.;10Jun.2019; J.vanSteenisleg.;JSB,2019-00.988,2019-00.989•6♀♀;samedataasforpreceding;JSB,201900.990to2019-00.995•4♀♀;samedataasforpreceding;X.Mengualleg.;ZFMK,ZFMKDIP-00066520toZFMK-DIP-00066523•1♂,1♀;Abastumani;41.8242°N,42.8472°E;2150ma.s.l.; 10Jun.2019;F.VandeMeutterleg.;FMT•1♂;BorjomiN.P.;41.86°N,42.77°E;1830ma.s.l.; 10Jun.2019;J.vanSteenisleg.;JSB,2019-00.996•4♀♀;samedataasforpreceding;JSB,201900.997to2019-00.999,2019-01.000•4♂♂;samedataasforpreceding;X.Mengualleg.;ZFMK, ZFMK-DIP-00066562,ZFMK-DIP-00066563,ZFMK-DIP-00066566,ZFMK-DIP-00066567•4♀♀; same data as for preceding; ZFMK, ZFMK-DIP-00066537 to ZFMK-DIP-00066539, ZFMKDIP-00066552=ZFMK-TIS-8006833•1♀;BorjomiN.P.;41.823°N,42.841°E;2049ma.s.l.;11Jun. 2019;S.Botleg.;SBA,SB.003016•3♂♂;BorjomiN.P.;41.8181°N,42.8316°E,2004ma.s.l.;11Jun. 2019;J.H.Skevingtonleg.;CNC,CNC1386282,CNC1386296,CNC1386300•3♀♀;samedataasfor preceding;CNC,CNC1386250,CNC1386284,CNC1386290•2♀♀;BorjomiN.P.;41.8697°N, 42.7923°E;1683ma.s.l.,11Jun.2019;J.H.Skevingtonleg.;CNC,CNC1386348,CNC1386350• 2♀♀;BorjomiN.P.;41.82°N,42.84°E;2100ma.s.l.;11Jun.2019;J.vanSteenisleg.;JSB,201901.001,2019-01.002•5♂♂;BorjomiN.P.;41.8245°N,42.8482°E;2165ma.s.l.;11Jun.2019; J.H. Skevington leg.; CNC, CNC1386088, CNC1386093, CNC1386094, CNC1386107, CNC1386143 European Journal of Taxonomy 1023: 1–181 (2025) 20 •16♀♀;samedataasforpreceding;CNC,CNC1386087,CNC1386099,CNC1386100,CNC1386103, CNC1386108, CNC1386109, CNC1386122 to CNC1386125, CNC1386132, CNC1386136, CNC1386138toCNC1386140,CNC1386145•3♂♂;BorjomiN.P.;41.8234°N,42.84°E,2025ma.s.l.; 11Jun.2019;X.Mengualleg.;ZFMK,ZFMK-DIP-00066559toZFMK-DIP-00066561•3♀♀;same data as for preceding; ZFMK, ZFMK-DIP-00066531 = ZFMK-TIS-8008825, ZFMK-DIP-00066532, ZFMK-DIP-00066533•3♀♀;BorjomiN.P.;41.863°N,42.789°E;1800ma.s.l.;11Jun.2019; X. Mengual leg.; ZFMK, ZFMK-DIP-00066540, ZFMK-DIP-00066541, ZFMK-DIP-00066550 = ZFMK-TIS-8008827•2♂♂;Sakire,41.7301°N,43.3306°E;1820ma.s.l.;10May2023;F.Vande Meutterleg.;FMT•1♂;Dviri,41.7543°N,43.2734°E;1090ma.s.l.;10May2023;F.VandeMeutter leg.;FMT•1♀;Kodiani;41.7300°N,43.3485°E;2080ma.s.l.;10May2023;W.Opdekampleg.; WOR,A027•1♂;Dviri;41.7543°N,43.2733°E;1100ma.s.l.;10May2023;W.Opdekampleg.; WOR,D011•2♂♂;Dviri;41.7543°N,43.2734°E;1090ma.s.l.;12May2023;F.VandeMeutterleg.; FMT•3♀♀;samedataasforpreceding;FMT,ZFMK-TIS-8028473•1♀;Borjomi;41.8098°N, 43.3327°E;850ma.s.l.;12May2023;W.Opdekampleg.;WOR,A019•2♂♂;Dviri;41.7543°N, 43.2733°E;1100ma.s.l.;12May2023;W.Opdekampleg.;WOR,B027,B029•1♀;samedataasfor preceding; WOR, B010. TURKEY – Rize•10♂♂;NsideofOvitGeçidi;1800ma.s.l.;19Jul.1992;J.A.W.Lucasleg.;RMNH, ZMA.INS.1451007toZMA.INS.1451011,ZMA.INS.1451053toZMA.INS.1451057•18♀♀;same data as for preceding; NBC, ZMA.INS.1451012 to ZMA.INS.1451016, ZMA.INS.1451058 to ZMA. INS.1451070. Description Male Length. Body 9–12.5 mm, wing 8.5–10.5 mm. head. Face bare, black, slightly protruding downwards, with facial tubercle, facial tubercle distinct, rounded and placed relatively low on the face, thick pruinose below lunule, facial tubercle shiny, area ventral of facial tubercle slightly pruinose or shiny, below lunule narrower than an eye. Mala black, shiny. Parafacia black, pruinose or shiny, white pilose, about 0.8 times as wide as postpedicel. Clypeus shiny or slightly pruinose, about twice as long as wide. Frontal triangle black, shiny, except narrowly pruinose along eye margin, swollen, with long black pile, sometimes with yellow pile intermixed, with medial frontal sulcus. Length of eye contiguity about 1.2 times the length of frons. Angle of approximation of eyes90–110°.Verticaltriangleblack,shiny,ocellartriangleshiny,longblackpilose.Occiputpruinose, short yellow and long black pilose. Lunule dark orange to blackish, with distinct medial arm, separating acetabula. Scape black, anteriorly with black setae; pedicel black at base, dark orange at apex, anteriorly with black setae; postpedicel bright orange, sometimes apicodorsal corner darkened, rounded, pruinose, about as heigh as wide or slightly wider as high; arista black, sometimes very base dark orange, with very short pile, pile much shorter than diameter of arista at base. Eye with long, black and dense pile. thorax.Scutumblack,shiny,finelypunctured,anteriorlywithlongerectpile,posteriorlywithlong erect and short erect pile, pile whitish or golden yellow except in anterolateral corners and posterior half with variable amount of black pile. Scutellum shiny, with long erect and denser short erect pile, pile black except long pile along posterior margin yellow, without black setae along posterior margin. Pleura black, slightly pruinose, pile yellowish except on anepisternum where predominantly black and on anepimeron where sometimes partly or predominantly black; metasternum with long whitish pile; dorsal and ventral pile patches on katepisternum connected by shorter pile. Haltere pedicellum orange, capitulum dark brown to blackish. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 21 Wing. Wing including alula entirely microtrichose, hyaline except in some specimens where anterior and basal parts slightly yellow-brown infuscate, wing veins brown in the basal part and black in the apical part of the wing. Legs. Coxae and trochanters black. Femora black except apices narrowly yellow; profemur anteriorly with short semi-adpressed golden pile, posteriorly with long black pile; mesofemur anteriorly with pile of decreasing length towards apex, predominantly golden at base, black at apex, posteriorly with long predominantly black pile; metafemur anteriorly and anteroventrally with row of, predominantly golden, long pile, ventrally with short semi-adpressed black pile, golden at base, posteriorly with short erect predominantlygoldenpile.Protibiaorangeexceptcentralfifthtohalfofposteriorsidewithblackish marking, anteriorly with dense adpressed golden pile, posteriorly with semi-adpressed black pile; mesotibiaorangewithvariablevaguelydelimitedblackishringbelowthemiddleoccupyingafifthto three-quarters of tibia length, with short black pile; metatibia orange at basal third and at very apex, in between with black ring or dark orange to blackish markings, sometimes black markings reduced to Fig. 8. Cheilosia (Cheilosia) aurantia sp. nov. A–B.Holotype,♂(ZFMK,ZFMK-DIP-00066574); habitus, lateral and dorsal views; body length 10.2 mm. C–D. Paratype, ♀ (ZFMK, ZFMKDIP-00066543); habitus, lateral and dorsal views; body length 11.0 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 22 black smudge, ventrally with adpressed dense golden pile, most extensive at apex, anteriorly with semierect black pile, posteriorly with adpressed pile, basally for third to two thirds black, remainder golden; protarsus with basal four tarsomeres orange, dark orange or blackish dorsally, orange ventrally, tarsomere 5 black, with golden pile, except dorsally with black pile; mesotarsus with basal four tarsomeres dark orange or blackish dorsally, orange or dark orange ventrally, tarsomere 5 black, with black pile, ventrally with black setae; metatarsus black or blackish dorsally, ventrally basal four tarsomeres dark orange or blackish, tarsomere 5 black, with black pile, except basal three tarsomeres dorsally and posteriorly with dense adpressed golden pile, basitarsomere not swollen. abdomen. Terga I–IV with erect long golden pile, except posterior margin of terga II–IV where slightly adpressed, sometimes with narrow area of black pile along front margin of terga III and IV and with scattered black pile medially on posterior half of tergum III and in posterior corners of tergum IV; tergum I pruinose, tergum II and III slightly pruinose except shiny lateral margins, tergum IV anteriorly and medially with slight pruinosity, otherwise shiny. Sternum I pruinose, sometimes with median shiny stripe, with long erect yellow pile, becoming laterally shorter and more adpressed, sternum II shiny with long erect yellow pile, sternum III shiny, medially with short adpressed pile, laterally with long erect pile, sternum IV with very slight pruinosity, medially with short adpressed pile, laterally with long erect pile. Genitalia with surstylus ca 1.7 times as long as wide, with large keel, keel and area above keel with large fieldofmicrotrichia(Fig.9D);dorsallobeofpostgoniteshortandwidewithinwardsfacingtip(Fig.9C). Female Length. Body 7.5–10 mm, wing 8–9.5 mm. Similar to the male, except for normal sexual dimorphism and the following characters. Frons shiny except anterolateral corners with small triangular area of grey pruinosity, with erect golden pile, along lateral margins sometimes with few black pile, with wide paravertica. Pile on ocellar triangle variable, golden, black or intermixed golden and black. Dorsal third of occiput shiny along eye. Scape blackish to orange, anteriorly with black or yellow setae. Pedicel blackish to orange. Colour of pile on eye yellow or dorsal part brown or black, ventral part yellow. Scutum with erect dense golden or whitish pile, of twolengthsonposteriorpart,shortpileonposteriorpartsometimeswithfieldofblackpile.Scutellum shiny, with long golden pile and short golden pile or mixed golden and black pile. Pleura with yellow pile, sometimes with a few individual black pile on posterior anepisternum. Capitulum of haltere orange to brownish. Femora orange. Profemur posteriorly with long black or yellow or mixed pile. Mesofemur posteriorly with long predominantly yellow pile. Metafemur with yellow pile, sometimes with few black setae ventrally near apex. Tibia orange, with whitish pile, sometimes with few individual black pile. Protarsus with basal four tarsomeres orange, tarsomere 5 black, with yellow pile. Mesotarsus with basal four tarsomeres orange, tarsomere 5 black, with yellow pile. Metatarsus with tarsomere 1 dorsally black, ventrally orange, tarsomere 2 and 3 orange, with or without black base dorsally, tarsomere 4 dorsally black, ventrally orange, tarsomere 5 black. Terga I–IV completely covered with yellow pile, long and erect along lateral margins, adpressed and shorter medially. Terga II–IV shiny. Sternum IV shiny except posterior margin pruinose. Morphological variation There is a female (ZFMK-DIP-00066552 = ZFMK-TIS-8006833) with long pile on the face and another female has the femora predominantly black. Moreover, there is a male with the tibiae completely yellow. Genetics All DNA barcodes of C. aurantia sp. nov. are resolved into a cluster with high support (BS = 100%). BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 23 Remarks This species has been named in the published literature as C. lenis. In fact, some paratypes collected in 2018wereidentifiedasC. lenis by Mengual et al. (2020). In2023,thefirstauthorfoundaseriesofC. aurantia sp. nov. in the collection of the RMNH. The specimens were collected by J.A.W. Lucas in Turkey in 1992. The series was labelled in the box as “Cheilosia pontica sp. nov. Claussen & Lucas”, but the species and the name were never published. We assembled the series of paratypes of C. aurantia. We would have been happy to adopt the working name of C. pontica of Claussen and Lucas, however, this name refers to the region in Turkey where these specimens were found, while we now know that the species has a much wider distribution, throughout the Caucasus. Fig. 9. Cheilosia (Cheilosia) aurantia sp. nov. A.Holotype,♂(ZFMK,ZFMK-DIP-00066574);head, lateral view; eye width 1.5 mm. B.Paratype,♀(ZFMK,ZFMK-DIP-00066531);head,lateralview; eye width 1.4 mm. C.Paratype,♂(SBA,SB.003018);surstylus,lateralview.D.Paratype,♂(SBA, SB.003018); postgonite, lateral view. Scale bars: A–B not to scale; C–D in µm. European Journal of Taxonomy 1023: 1–181 (2025) 24 Biology Common, collected in mountains at altitudes between 612–2615 m a.s.l. Early in the season found on Taraxacum sp., Salixsp.catkinsandfloweringAcer velutinumBoiss.,lateronavarietyoflowflowers including Ranunculus sp. and Caltha palustris. Females have been observed to crawl downwards along the leafstem of Caucasalia macrophylla (M.Bieb.) B.Nord. which may indicate that this is the larval food plant. Distribution InTurkeyonlyknownfromthehighmountainpassOvitDağıGeçidi.OutsideTurkeywidespreadinthe Greater and Lesser Caucasus, known from Armenia, Georgia and Russia. Cheilosia (Taeniochilosia) bakurianiensis Kuznetzov, 1987 Fig. 10 Cheilosia bakurianiensis Kuznetzov, 1987: 432. Cheilosia bakurianiensis – Barkalov 1993: 708. — Barkalov & Ståhls 1997: 16. — Mengual et al. 2020: 25. Differential diagnosis Cheilosia bakurianiensis belongs to the subgenus Taeniochilosia by the combination of bare eye, black legsandtheanteriorprocessoflunulanotbroadlyconfluentwiththeface(Barkalov&Ståhls1997). Within TaeniochilosiaoccurringintheCaucasus,themalecanbeidentifiedbythecombinationof pruinose sterna and shiny parafacia. The female is easily separated from the other Taeniochilosia taxa occurring in the Caucasus by the wide face, broader than an eye at level of antennal base. Material examined Not collected in 2018, but collected in 2019, 2022 and 2023. ARMENIA – Kotayk Province•28♂♂;Tsaghkadzorarea;40.52837°N,44.68951°E;2220ma.s.l.; 24 May 2022; X. Mengual leg.; ZFMK, ZFMK-DIP-00093702 to ZFMK-DIP-00093709, ZFMKDIP-00093711, ZFMK-DIP-00093712 = ZFMK-TIS-8014585, 8008756ZFMK-DIP-00093713 = ZFMK-TIS-8014582, ZFMK-DIP-00093714 to ZFMK-DIP-00093720, ZFMK-DIP-00093722 = ZFMK-TIS-8014583, ZFMK-DIP-00093723 to ZFMK-DIP-00093727, ZFMK-DIP-00093729 = ZFMK-TIS-8014584,ZFMK-DIP-00093784toZFMK-DIP-00093786•64♀♀;samedataasfor preceding; ZFMK, ZFMK-DIP-00093730 to ZFMK-DIP-00093737, ZFMK-DIP-00093739 to ZFMK-DIP-00093744, ZFMK-DIP-00093746 to ZFMK-DIP-00093748, ZFMK-DIP-00093749 = ZFMK-TIS-8014586, ZFMK-DIP-00093750, ZFMK-DIP-00093752 to ZFMK-DIP-00093756, ZFMK-DIP-00093758, ZFMK-DIP-00093759, ZFMK-DIP-00093760 = ZFMK-TIS-8014587, ZFMK-DIP-00093761 to ZFMK-DIP-00093763, ZFMK-DIP-00093765 to ZFMK-DIP-00093769, ZFMK-DIP-00093771 to ZFMK-DIP-00093775, ZFMK-DIP-00093777 to ZFMK-DIP-00093783, ZFMK-DIP-00093787, ZFMK-DIP-00093788, ZFMK-DIP-00093790 to ZFMK-DIP-00093792, ZFMK-DIP-00093794, ZFMK-DIP-00093796 to ZFMK-DIP-00093806. – Syunik Province•3♀♀; Spandaryan,smallriver;39.621045°N,45.910242°E;1986ma.s.l.;19May2022;X.Mengualleg.; ZFMK, ZFMK-DIP-00093194 = ZFMK-TIS-8014648, ZFMK-DIP-00093237, ZFMK-DIP-00093238. GEORGIA•Samtskhe-Javakheti–4♂♂;roadfromSakiretoTsikhisjvari;41.7251°N,43.3605°E; 2519 m a.s.l.; 9 Jun. 2019; X. Mengual leg.; ZFMK, ZFMK-DIP-00066354 = ZFMK-TIS-8008759, ZFMK-DIP-00066355, ZFMK-DIP-00066356 = ZFMK-TIS-8008760, ZFMK-DIP-00066363 = ZFMKTIS-8008756•6♀♀;samedataasforpreceding;ZFMK,ZFMK-DIP-00066357,ZFMK-DIP-00066358, BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 25 Fig. 10. Cheilosia (Taeniochilosia) bakurianiensis Kuznetzov, 1987. A.♂(FMT);habitus,lateralview; collected in Georgia; body length 7.0 mm. B.♂(FMT);head,lateralview;collectedinGeorgia;eye width 1.1 mm. C.♂(FMT);collectedinGeorgia;habitus,dorsalview;collectedinGeorgia;bodylength 7.3 mm. D.♀(FMT);head,lateralview;collectedinGeorgia;eyewidth1.0mm.E.♀(ZFMK, ZFMKDIP-00093761); head, frontal view; collected in Armenia; facial width 2.1 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 32 Female Length. Body 9.5–13 mm, wing 10–11.5 mm. Similar to the male, except for normal sexual dimorphism and the following characters. Face with entirely yellow pile. Frons with short yellow pile, with longer black pile intermixed. Scutum shiny except lateral margins widely slightly pruinose, with shorter semi-adpressed yellow and black pile and with sparse longer more erect black pile. Scutellum shiny, with pile of two lengths, variable black or yellow short pile and long black pile. Pleura with yellow pile. Procoxa usually with yellow pile and setae only. Femora with predominantly yellow pile, sometimes with a few black setae on ventral side on metafemur. Pile on terga shorter and black pile more extensive. Pile on sterna shorter, without black pile. Fig. 13. Cheilosia (Cheilosia) borjomi sp. nov. A–B.Holotype,♂(ZFMK,ZFMK-DIP-00066260); habitus, lateral and dorsal views; body length 10.4 mm. C–D. Paratype, ♀ (ZFMK, ZFMKDIP-00066271); habitus, lateral and dorsal views; body length 10.7 mm. Not to scale. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 33 Morphological variation One female (ZFMK-DIP-00093664 = ZFMK-TIS-8014603) is markedly different by having much less black pile in general, all pale pile very bright golden yellow instead of whitish, and tibiae yellow at both ends instead of tibiae black. Genetics All DNA barcodes of C. borjomi sp. nov. are resolved into one cluster without high support (BS < 90%). Fig. 14. Cheilosia (Cheilosia) borjomi sp. nov. A.Holotype,♂(ZFMK,ZFMK-DIP-00066260);scutum, lateral view; scutum length 3.0 mm. B.Paratype,♀(ZFMK,ZFMK-DIP-00066271);scutum,lateral view; scutum length 3.1 mm. C.Paratype,♂(ZFMK,ZFMK-DIP-00066254);forecoxae,anteriorview; coxa length 1.2 mm. D–E.Paratype,♂(SBA,SB.003074).D. Postgonite, lateral view. E. Surstylus, lateral view. Scale bars: A–C not to scale; D–E in µm. European Journal of Taxonomy 1023: 1–181 (2025) 34 Remarks Some records of C. variabilis in Mengual et al. (2020) actually represents C. borjomi sp. nov., and are reported here again as C. borjomi. Biology Collected between 530–2260 m a.s.l. on extensive grasslands and in or near forest, where it feeds on low flowers.ThisspeciescanbefoundinsympatrywithC. variabilis in Borjomi National Park. Distribution So far only known from the Lesser and Greater Caucasus in Armenia and Georgia. Mainly recorded in the Lesser Caucasus, with only a very few records from the Greater Caucasus. Cheilosia (Cheilosia) bracusiVujić&Claussen,1994 Fig. 15 Cheilosia bracusi Vujić&Claussen,1994:137. Cheilosia bracusi – Mengual et al. 2020: 15. Fig. 15. Cheilosia (Cheilosia) bracusi Vujić&Claussen,1994.CollectedinGeorgia.A.♂(FMT); habitus, lateral view; body length 10.0 mm. B.♂(FMT);head,lateralview;eyewidth1.4mm. C.♂(SBA,ZFMK-TIS-8027987);habitus,dorsalview;bodylength9.8mm.D.♀(FMT);head,lateral view; eye width 1.3 mm. Not to scale. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 35 Differential diagnosis Cheilosia bracusi has a pilose eye, bare face, bicoloured legs, posterior margin of scutellum with setae (although often short and yellow in the female) and sterna shiny. Many species of Cheilosia have this combination of characters, but it can be distinguished from most of them by the eye being entirely pilose (ventral part bare or nearly so in C. bergenstammi), arista black (orange in C. chloris (Meigen, 1823)) and body size at least 8 mm (in C. vernalis at most 8 mm). For differences with very similar extralimital C. melanuraBecker,1894,seeVujić&Claussen(1994).WithintheCaucasus,itcanbeconfusedmainly with C. confusa sp. nov. A general distinct characteristic is the colour of the pale body pile, rufous in C. bracusi, whitish or yellow in C. confusa. Moreover, the metatibia in C. bracusi has a narrow or incomplete black ring covering less than half of metatibia (Fig. 15A) (with broad black ring covering ca half of tibia in C. confusa) and mesotarsus with basal two or three tarsomeres yellow (tarsi dorsally black in C. confusa).ThemalegenitaliaarefiguredinVujić&Claussen(1994). Material examined Collected in 2018, 2019 and 2023; see Mengual et al. (2020) for detailed records from 2018. Genetics DNA barcodes of C. bracusi are placed into a cluster without high support (BS < 90%), grouped with some barcodes of C. melanura. Biology During our expeditions, collected between 6 May and 19 June at an altitude between 1090 and 2327ma.s.l.Visitsbothlowflowers(Ranunculussp.)asfloweringshrubsandtrees(Acer velutinum, Salix sp., Sorbus sp.) in or at the edge of meadows, including dry slopes. Distribution Southern and Central Europe, Balkan Peninsula, and Caucasus. Within the Caucasus only reported from Georgia. Cheilosia (Cheilosia) brunnipennis Becker, 1894 Fig. 16 Chilosia brunnipennis Becker, 1894: 417. Chilosia sareptanaBecker,1894:418.Syn.byVujić(1996). Chilosia brunnipennis – Barkalov & Mutin 2018: 482. — Mengual et al. 2020: 15. Chilosia sareptana – Stackelberg & Richter 1968: 248. — Stackelberg 1970: 61. — Peck 1988: 116. — Barkalov 1993: 718. Differential diagnosis Cheilosia brunnipennis is similar to C. flavipes, C. megaclama sp. nov., and C. nebulosa, sharing a pilose eye (but eye bare in female C. flavipes and female C. megaclama), bare face, lack of setae on posterior margin of scutellum, bicoloured legs and dorsal and ventral pile patches on katepisternum widely separated. The male C. brunnipenniscanimmediatelybeidentifiedfromallthreebythelong postpedicel (Fig. 16B), ca two times as wide as high (rounded in the other three species). Moreover, the male of C. brunnipennis has basal three or four tarsomeres of protarsus yellow (Fig. 16C) (protarsus dorsally black in C. megaclama), arista black (at least the base extensively orange in C. nebulosa), and frons swollen (not swollen in C. flavipes). In the female the eye is pilose (bare in C. flavipes and European Journal of Taxonomy 1023: 1–181 (2025) 36 C. megaclama), arista black (at least the base extensively orange in C. nebulosa), postpedicel large and parafacia wide (postpedicel small and parafacia narrow in C. nebulosa). Material examined Not collected in 2018, but collected in 2023. GEORGIA – Mtskheta-Mtianeti•1♀;TbilisiN.P.;41.877°N,45.0138°E;1250ma.s.l.;4May2023; F. Van de Meutter leg.; FMT, ZFMK-TIS-8027947. – Samtskhe-Javakheti•1♀;Borjomi;41.8098°N, 43.3327°E;850ma.s.l.;12May2023;W.Opdekampleg.;WOR,A001=ZFMK-TIS-8028456. Genetics DNA barcodes of this species are recovered into a cluster with high support (BS = 100%). Biology During our expeditions, collected between 4 May and 12 May at an altitude between 850 and 1250 m a.s.l., visiting Ranunculus sp. and Salix sp. Fig. 16. Cheilosia (Cheilosia) brunnipennis Becker, 1894. A.♂(SBA,SB.004463);habitus,lateral view; collected in Greece; body length 9.5 mm. B.♂(SBA,SB.004463);head,lateralview;collected in Greece; eye width 1.4 mm. C.♂(SBA,SB.004463);habitus,dorsalview;collectedinGreece;body length 9.5 mm. D.♀(FMT,ZFMK-TIS-8027947);head,lateralview;collectedinGeorgia;eyewidth 1.3 mm. Not to scale. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 37 Distribution Western Palaearctic. Within the Caucasus known from Armenia, Georgia and Russia. Cheilosia (Cheilosia) canicularis (Panzer, 1801) Fig. 17 Syrphus canicularis Panzer, 1801: 20. Cheilosia canicularis – Radde 1899: 453. — Stackelberg & Richter 1968: 245. — Stackelberg 1970: 61. — Peck 1988: 99. — Barkalov 1993: 721. — Mengual et al. 2020: 15. — Żóralski 2022: 68. Cheilosia canicularis Panzer, 1798 [sic] – Gujabidze 2002: 245. Differential diagnosis Cheilosia canicularis is a large Cheilosia (13–15 mm) that lacks setae on the posterior margin of the scutellum and has pilose eyes in the dorsal half, but only sparsely pilose or bare in the ventral half. This Fig. 17. Cheilosia (Cheilosia) canicularis (Panzer, 1801). Collected in Georgia. A.♂(SBA,SB.002251); habitus, lateral view; body length 13.8 mm. B.♂(SBA,SB.002263);head,lateralview;eyewidth1.6mm. C.♂(SBA,SB.002251);habitus,dorsalview;bodylength14.1mm.D.♀(SBA);head,lateralview;eye width 1.7 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 38 combination of characters can only be found in the morphologically very similar C. himantopus, and onlyrelativelyrecentlytheiridentificationandstatuswasclarified(Stuke&Claussen2000).Cheilosia canicularisisaspeciesflyinginsummer,whileC. himantopus occurs in spring, with some overlap in June. Cheilosia canicularis has pile on arista about as long as diameter of arista (half as long as diameter of arista in C. himantopus).Inthemale,usually(butnotalways)thefifthtarsomereisyellow(atleast fifthtarsomereblackinC. himantopus) and there are subtle differences in the genitalia, see Stuke & Claussen (2000). In the female, posterior margin of tergum III with complete band of dense, adpressed pile (with sparse, incomplete band of adpressed pile in C. himantopus) and posterior third of tergum IV with dense, adpressed pile (with scattered, semi-adpressed pile in C. himantopus). For differences with C. orthotricha, see Differential diagnosis under that species. Material examined Collected in 2018, 2019 and 2021; see Mengual et al. (2020) for detailed records from 2018. Genetics We recovered a cluster (BS = 99.8%) with the barcodes of C. canicularis and the sequences of C. himantopus. Although some structure can be seen in the arrangement of the molecular data, both species cannot be distinguished with certainty from DNA barcodes. Biology During our expeditions, collected between 27 June and 9 September at an altitude between 790 and 2887 m a.s.l. on meadows and in forest clearings. Distribution Central Europe, Turkey and the Caucasus. Within the Caucasus known from Armenia, Georgia and Russia. Cheilosia (Cheilosia) caucasi sp. nov. urn:lsid:zoobank.org:act:D45D45B8-84F8-4D18-A6DB-8ABAAEEDAE91 Figs 18–19 Differential diagnosis Cheilosia caucasi sp. nov. most closely resembles C. abagoensis, C. gemmula sp. nov. and C. rhynchops. Both sexes look like C. rhynchops but face not protruding, facial tubercule not low on face (in C. rhynchops the face is protruding, with facial tubercle low on face), postpedicel black (Fig. 19A–B) (postpedicel usually orange basoventrally in C. rhynchops), pleura predominantly with black pile (with extensive yellow pile in C. rhynchops), dorsal and ventral pile patches on katepisternum widely separated (variable in C. rhynchops, but in the Caucasian populations these piles are connected by short pile medially). Male differs further from C. rhynchops in having parafacia wider, frons partly pruinose and not swollen (shiny and swollen in C. rhynchops), occiput dorsally with mixed black and yellow pile (black in C. rhynchops), eye with less dense, shorter and paler pile, scutum shiny (pruinose on anterior third in C. rhynchops), scutum with less extensive white pile (Fig. 18A) and surstylus with microtrichia on dorsal part (Fig. 19D) (without microtrichia in C. rhynchops). See the differential diagnosis of C. gemmula for differences between that species and C. caucasi. The new species C. caucasi is similar to C. abagoensis but thorax with black instead of blue-black shine, eye usually with sparser and partly yellow pile (eye with black and dense pile in C. abagoensis),scutumfinelypunctured(scutumcoarselypuncturedin C. abagoensis), pleura pruinose (largely shiny in C. abagoensis), wing hyaline (blackish infuscated in C. abagoensis, Fig. 1C), and sternum I largely or entirely pruinose (sternum I largely or entirely shiny in C. abagoensis). Males of C. caucasi can have sterna quite pruinose, in that case it may look like BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 39 C. teberdensis and C. paragigantea, however, the katepisternal pile patches are separated as mentioned above in our new species, but connected in C. teberdensis and C. paragigantea. In some cases, females of C. caucasi have bare eyes resembling females of the subgenus Taeniochilosia, but the anterior process ofthelunuleisbroadlyconfluentwiththeface(anteriorprocessmissinginTaeniochilosia). Etymology The species name is derived from ‘Caucasus’ and can be translated as ‘the Cheilosia of the Caucasus’. Species epithet to be treated as a noun in the genitive case. Material examined Holotype GEORGIA•♂;Samtskhe-Javakheti,roadfromSairmetoTsikhisjvari,hilltopandsurroundings; 41.7251°N,43.3605°E;2519ma.s.l.;9Jun.2019;X.Mengualleg.;ZFMK,ZFMK-TIS-8008778= ZFMK-DIP-00066397. Paratypes GEORGIA – Imereti•1♂;roadfromAbastumanitoSairme;41.8385°N,42.8194°E;2260ma.s.l.; 10Jun.2019;X.Mengualleg.;ZFMK,ZFMK-DIP-00066400=ZFMK-TIS-80087812•2♀♀;road fromAbastumanitoSairme;41.8385°N,42.8194°E;2260ma.s.l.;10Jun.2019;F.VandeMeutterleg.; FMT•4♂♂;roadfromAbastumanitoSairme;41.8245°N,42.8482°E;2165ma.s.l.;10Jun.2019; J.H. Skevington leg.; CNC, CNC1386101, CNC1386104 to CNC1386106. – Kakheti•1♂;Lagodekhi N.P.;41.88273°N,46.32185°E;1841ma.s.l.;3May2014;G.Japoshvilileg.;CNC,CNC1547273• 2♂♂;BatsaraNatureReserve;42.286542°N,45.242212°E;2065ma.s.l.;29May2022;X.Mengual leg.; ZFMK, ZFMK-DIP-00094028 = ZFMK-TIS-8014638, ZFMK-DIP-00094029 = ZFMKTIS-8014639•1♀;BatsaraNatureReserve;42.264937°N,45.259187°E;1955ma.s.l.;29May2022; X. Mengual leg.; ZFMK, ZFMK-DIP-00094021 = ZFMK-TIS-8014637. – Mtskheta-Mtianeti•1♂; Lutkhubi;42.3930°N,44.7929°E;1700ma.s.l.;6May2023;W.Opdekampleg.;WOR,A012•2♂♂; Lutkhubi;42.3797°N,44.7969°E;1463ma.s.l.;6May2023;S.Botleg.;SBA,SB.003115=ZFMKTIS-8027988,SB.003116•2♂♂,4♀♀;Sno;42.6156°N,44.6148°E;1850ma.s.l.;7May2023;F.Van deMeutterleg.;FMT•1♂;Lutkhubi;42.3936°N,44.7923°E;1760ma.s.l.;8May2023;F.Vande Meutterleg.;FMT•1♂;Lutkhubi;42.3930°N,44.7929°E;1734ma.s.l.;8May2023;W.Opdekamp leg.;WOR,C006•1♂;Lutkhubi;42.3936°N,44.7923°E;1760ma.s.l.;8May2023;F.VandeMeutter leg.; FMT. – Racha-Lechkhumi and Kvemo Svaneti•2♀♀;42.909°N,43.142°E;1900ma.s.l.; 29Jun.2018;S.Botleg.;SBA,SB.003087,SB.003088•2♀♀;42.888°N,43.233°E;1900ma.s.l.; 30Jun.2018;S.Botleg.;SBA,SB.003096,SB.003097•1♀;42.820°N,43.159°E;1400ma.s.l.;2Jul. 2018;S.Botleg.;SBA,SB.003105•1♂;nearShovi;42.665°N,43.656°E;2203ma.s.l.;10Jul.2021; S. Bot leg.; SBA, SB.003110. – Samegrelo-Zemo Svaneti•2♂♂;42.950°N,43.075°E;2275ma.s.l.; 24Jun.2018;S.Botleg.;SBA,SB.003091,SB.003092•1♂;42.948°N,43.021°E;2800ma.s.l.; 25Jun.2018;S.Botleg.;SBA,SB.003090•1♀;42.897°N,43.008°E;2630ma.s.l.;28Jun.2018; S.Botleg.;SBA,SB.003089•1♀;Ushguli;42.916°N,43.018°E;2140ma.s.l.;29Jun.2018;S.Bot leg.;SBA,SB.003086•1♂;Mestia;43.028°N,42.910°E;2834ma.s.l.;13Jun.2019;S.Botleg.; SBA,SB.003106•1♀;samedataasforpreceding;SBA,SB.003107•2♂♂;43.0254°N,42.8906°E; 2550 m a.s.l.; 13 Jun. 2019; X. Mengual leg.; ZFMK, ZFMK-DIP-00066402 = ZFMK-TIS-8008783, ZFMK-DIP-00066403•3♂♂,2♀♀;43.0254°N,42.8906°E;2550ma.s.l.;13Jun.2019;F.Vande Meutterleg.;FMT•1♀;43.0265°N,42.9100°E;2860ma.s.l.;13Jun.2019;X.Mengualleg.;ZFMK, ZFMK-DIP-00066404=ZFMK-TIS-8008784•1♀;43.0259°N,42.9103°E;2871ma.s.l.;13Jun. 2019;J.H.Skevingtonleg.;CNC,CNC1386375•3♂♂;Mestia;43.02°N,42.89°E;2600ma.s.l.; 13Jun.2019;J.vanSteenisleg.;JSB,2019-00.959,2019-01.087,2019-01.088=ZFMK-TIS-8009607• 1♀;42.948°N,43.070°E;2258ma.s.l.;15Jun.2019;S.Botleg.;SBA,SB.003108•1♂;42.9471°N, 43.0671°E;2257ma.s.l.;15Jun.2019;J.H.Skevingtonleg.;CNC,CNC1386526•1♀;samedataas forpreceding;CNC,CNC1386527•1♂,1♀;42.9062°N,42.9370°E;2615ma.s.l.;16Jun.2019; European Journal of Taxonomy 1023: 1–181 (2025) 40 F.VandeMeutterleg.;FMT•1♀;42.900°N,42.934°E;2700ma.s.l.;17Jun.2019;S.Botleg.;SBA, SB.003109=CNCdatabasingS.Bot922=CNCTW077-21=JSM13473•2♂♂;2kmSWofUshguli; 43.0052°N,42,8986°E,2550ma.s.l.;17Jun.2019;F.VandeMeutterleg.;FMT•1♂;42.9140°N, 43.0911°E;2575ma.s.l.;18Jun.2019;X.Mengualleg.;ZFMK,ZFMK-DIP-00066401=ZFMKTIS-8008782•1♂;ZagarariPass;42.91°N,43.09°E;2585ma.s.l.;18Jun.2019;J.vanSteenis leg.;JSB,2019-01.146•1♀;42.9125°N,43.0549°E;2299ma.s.l.;11Jul.2021;S.Botleg.;SBA, SB.003111•2♀♀;42.9616°N,43.0914°E;2447ma.s.l.;12Jul.2021;S.Botleg.;SBA,SB.003112, SB.003113. – Samtskhe-Javakheti•1♂;BorjomiN.P.;41.867°N,43.251°E;2000ma.s.l.;18Jun. 2018;S.Botleg.;SBA,SB003094=CNCdatabasingS.Bot921=CNCTW076-21=JSM13472• 1♀;samedataasforpreceding;SBA,SB.003095•4♂♂;roadfromSakiretoTsikhisjvari;41.728°N, 43.364°E;2327ma.s.l.;9Jun.2019;S.Botleg.;SBA,SB.003098=CNCdatabasingS.Bot920, SB.003099toSB.003101•3♀♀;samedataasforpreceding;SBA,SB.003102toSB.003104•2♂♂, 5♀♀;roadfromSakiretoTsikhisjvari;41.7251°N,43.3605°E;2519ma.s.l.;9Jun.2019;F.Vande Meutterleg.;FMT•1♀;samedataasforpreceding;X.Mengualleg.;ZFMK,ZFMK-DIP-00066398= ZFMK-TIS-8008779•1♀;BorjomiN.P.;41.7280°N,43.3640°E;2327ma.s.l.;9Jun.2019;L.Hofstee leg.;LHH•1♂;roadfromSakiretoTsikhisjvari;41.7299°N,43.3684°E;2245ma.s.l.;9Jun.2019; J.H.Skevingtonleg.;CNC,CNC1386030•1♂;Borjomi;41.72°N,43.36°E;2250ma.s.l.;9Jun. 2019;J.vanSteenisleg.;JSB2019-01.022,ZFMK-TIS-8009606•1♀;samedataasforpreceding;JSB, 2019-01.073•1♂;Abastumani;41.83°N,42.81°E;2260ma.s.l.;10Jun.2019;J.vanSteenisleg.;JSB, 2019-01.075•1♀;BorjomiN.P.;41.823°N,42.841°E;2049ma.s.l.;11Jun.2019;S.Botleg.;SBA, SB.003093•1♀;BorjomiN.P.;41.8181°N,42.8316°E;2004ma.s.l.;11Jun.2019;J.H.Skevington leg.;CNC,CNC1386260•1♀;BorjomiN.P.;41.82°N,42.84°E;2100ma.s.l.;11Jun.2019;J.van Steenisleg.;JSB,2019-01.098,ZFMK-TIS-8009613•1♂;nearAkhalkalak;41.4672°N,43.4337°E; 1476ma.s.l.;19Jul.2021;S.Botleg.;SBA,SB.003114•21♂♂,1♀;Kodiani;41.7305°N,43.3537°E; 2160ma.s.l.;10May2023;F.VandeMeutterleg.;FMT•15♂♂;Kodiani;41.7300°N,43.3485°E; 2080 m a.s.l.; 10 May 2023; W. Opdekamp leg.; WOR, A004 to A007, A011, A012, A029 to A032, A036, A037,A042,A044,A046•3♀♀;samedataasforpreceding;WOR,A002,A008,A010. RUSSIA – North Ossetia-Alania•1♀;WofDigoria,ChefandzarmireinUrukhRivervalley; 42.9186°N,43.5149°E;2289ma.s.l.;2–3Jun.2018;A.Przhiboroleg.;yellowplates;ZFMK,ZFMKDIP-00078663 = ZFMK-TIS-8009570. – Kabardino-Balkaria•1♀;2–3kmSEofvill.Verkhnyaya Balkaria;43.0971°N,43.4795°E;1836ma.s.l.;7–8Jun.2018;A.Przhiboroleg.:yellowplates; ZFMK,ZFMK-DIP-00078650=ZFMK-TIS-8009593•1♀;2–3kmSEofvill.VerkhnyayaBalkaria; 43.0983°N,43.4777°E;1810ma.s.l.;7–8Jun.2018;A.Przhiboroleg.:yellowplates;DIP-00078655= ZFMK-TIS-8009599. Description Male Length. Body 8.5–11.5 mm, wing 6.5–9 mm. h ead . Face bare, black, with facial tubercle, slightly pruinose, densely pruinose below lunule, facial tubercle shiny. Parafacia black, pruinose, white pilose, about or almost as wide as length of postpedicel. Clypeus shiny or seldom slightly pruinose, 1.8 to 2.5 times as long as wide. Frontal triangle black, densely pruinose along eye margin and along face, otherwise slightly pruinose, with long black pile. Lengthofeyecontiguityaboutaslongaslengthoffrons.Angleofapproximationofeyesca90°. Vertical triangle black, shiny, ocellar triangle shiny, long black pilose, sometimes with small yellow pile intermixed. Occiput pruinose, short yellow and long black pilose. Lunule dark orange, with distinct medial arm, separating acetabula. Scape black, anteriorly with black setae; pedicel black, anteriorly with black setae; postpedicel black, rounded, pruinose, about as long as wide; arista black, basally with very short pile. Eyes with relatively sparse but long pile; colour of pile ranging from wholly dark yellow to black in dorsal part and yellow in ventral part. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 41 t horax .Scutumblack,shinyexceptnarrowlyanteriorly,finelypunctured,withlongerectblackpilosity, of two lengths in posterior part, anteriorly sometimes with some white pile. Scutellum shiny, with long and short black pile, sometimes also with short white pile, posterior margin with numerous black setae. Pleura black, slightly pruinose, with black pile except with white pile on proepisternum and metasternum and with white pile intermixed on katepisternum; dorsal and ventral pile patches on katepisternum widely separated. Haltere dark yellow to dark brown. Wing. Wing including alula entirely microtrichose, ranging from hyaline to with brown tinge in basal anterior part, veins black. Legs. Legs black, or in few specimens basal one-tenth of tibiae yellow. Coxae pruinose, procoxa with black pile, often intermixed with some yellow pile, anteriorly with black setae, sometimes intermixed with a few yellow setae; mesocoxa with black pile and setae, sometimes a few yellow pile or setae; metacoxa with mixed yellow and black pile, black pile often dominating. Trochanters black, with mixed black and yellow pile. Profemur with black pile except a few yellow pile anterolaterally; mesofemur Fig. 18. Cheilosia (Cheilosia) caucasi sp. nov. A–B.Holotype,♂(ZFMK,ZFMK-DIP-00066397); habitus, lateral and dorsal views; body length 9.2 mm. C–D.Paratype,♀(ZFMK,ZFMK-DIP-00066398); habitus, lateral and dorsal views; body length 9.4 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 48 Genetics Molecular data for C. triamilia Ballester-Torres et al., 2024, C. melanura, C. bracusi, C. gemmula sp. nov., C. vernalis and C. confusa sp. nov. cluster together without high support (BS < 90%) and relativelylowinterspecificp-distance(<0.022),exceptforthespecimenofC. vernalis ZFMKDIP-00093901(=ZFMK-TIS-8014645)thatreachesinterspecificp-distancesof0.0285(seeSupp.file3: Table S2). Nevertheless, all C. confusa barcodes cluster together (BS < 90%), the same for all DNA sequences of C. gemmula (BS < 90%). Fig. 22. Cheilosia (Cheilosia) confusa sp. nov. A, C–D.Holotype,♂(ZFMK,ZFMK-TIS-8028459). A. Head, lateral view; eye width 1.3 mm. B.Paratype,♀(WOR,ZFMK-TIS-8028461);head,lateral view; eye width 1.2 mm. C. Postgonite, lateral view. D. Surstylus, lateral view. Scale bars: A–B not to scale; C–D in µm. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 49 Remarks Specimens from the Caucasus published under the name C. melanura are considered to be records of C. confusa sp. nov. Two specimens which look intermediate between C. vernalis and C. confusa sp. nov. end up in the molecular tree near C. confusa (ZFMK-TIS-8009292, ZFMK-DIP-00093672 = ZFMK-TIS-8014649), butformingadifferentcluster(BS<90%).Weleavethesespecimensunidentified. Biology Seemingly mainly a spring species with most records in May and the last date on 10 June. Collected in highmountainsbetween2068–2280ma.s.l.,specimensfromMaywerefoundonfloweringwillowSalix sp.oronlowflowers. Distribution Endemic to the Caucasus, known from Georgia and Russia. Cheilosia (Montanocheila) contrasta sp. nov. urn:lsid:zoobank.org:act:75901346-020B-4D7A-9179-B179BFC02085 Figs 23–24 Differential diagnosis Cheilosia contrasta sp. nov. belongs to the subgenus Montanocheila. From all Montanocheila known from the Palaearctic Region (see Claussen 1998), the male differs by the following combination of characters: postpedicel predominantly orange (Fig. 24A), tibiae yellow at both ends (Fig. 23A), terga I–II with yellow pile contrasting with black pile on terga III–IV (Fig. 23A–B) and surstylus more than twice as long as wide, with pointed apex (Fig. 24D). In the male genitalia, the shape of the surstylus is very characteristic and only C. pictipennis Egger, 1860 has a similar looking surstylus; however, in C. contrasta sp. nov. the apex of the surstylus is more pointed (rounded in C. pictipennis). Moreover, both sexes can be distinguished from C. pictipennis by the uninterrupted long pilosity on anterior part of sternum II (in C. pictipennis the anterior part of sternum II is bare or short pilose medially) and by the characteristic bicoloured pilosity on abdomen, which is more variable in C. pictipennis. The female is very similar to that of C. subpictipennis, yet, the pile on terga III–V are long and black, while the pilosity on terga III–V is shorter and yellow in C. subpictipennis. Etymology The species name ‘contrasta’ refers to a characteristic feature of the species: the predominantly yellow pile on terga I–II contrasting sharply with the predominantly black pile on terga III–IV. Species epithet to be treated as an adjective. Material examined Holotype GEORGIA•♂;Imereti,roadfromAbastumanitoSairme;41.8380°N,42.8183°E;2260ma.s.l.;10Jun. 2019; X. Mengual leg.; ZFMK, ZFMK-TIS-8006786 = ZFMK-DIP-00066187. Paratypes ARMENIA – Ararat Province•1♀;surroundingsGeghardMonastery;40.1385°N,44.8172°E; 1720 m a.s.l.; 22 May 2022; X. Mengual leg.; ZFMK, ZFMK-DIP-00093557 = ZFMK-TIS-8014524; ZFMK. – Syunik Province•1♂;fromLichktotheZvaravankMonastery;39.0549°N,46.1713°E; 1765 m a.s.l.; 16 May 2022; X. Mengual leg.; ZFMK, ZFMK-DIP-00093035 = ZFMK-TIS-8014426. European Journal of Taxonomy 1023: 1–181 (2025) 50 GEORGIA – Adjara•1♂;KintrishiNatureReserve;41.75517°N,42.11249°E;2268ma.s.l.; 2–16 Jun. 2018; GGBC-members leg.; Malaise trap, stored in alcohol; ZFMK, ZFMK-TIS-8010561. – Kakheti–1♀;LagodekhiN.P.;41.8767°N,46.2429°E;615ma.s.l.;2May2023;S.Botleg.; SBA,SB.003118•1♀;LagodekhiN.P.;41.8777°N,46.2436°E;625ma.s.l.;2May2023;F.Vande Meutter leg.; FMT. – Mtskheta-Mtianeti•1♂;Lutkhubi;42.3797°N,44.7969°E;1463ma.s.l.;6May 2023;S.Botleg.;SBA,SB.003117•4♂♂;Lutkhubi;42.3936°N,44.7923°E;1760ma.s.l.;8May 2023; F. Van de Meutter leg.; FMT. – Samegrelo-Zemo Svaneti•1♂;Ushguli;42.950°N,43.075°E; 2275ma.s.l.;24Jun.2018;S.Botleg.;SBA,SB.003119=CNCdatabasingS.Bot649•2♂♂;Mestia; 43.1178°N,42.7251°E;1875ma.s.l.;14Jun.2019;F.VandeMeutterleg.;FMT•1♂;nearUshguli; 42.9498°N,43.0718°E;2270ma.s.l.;15Jun.2019;X.Mengualleg.;ZFMK,ZFMK-DIP-00066188= ZFMK-TIS-8006787•1♀;Ushguli;42.90°N,42.93°E;2600ma.s.l.;17Jun.2019;J.vanSteenisleg.; JSB,2019-00.888•1♀;Ushguli;42.898°N,42.008°E;2601ma.s.l.;18Jun.2019;S.Botleg.;SBA, SB.003120 = CNC databasing S Bot 917. – Samtskhe-Javakheti•1♀;Dviri;41.7543°N,43.2733°E; 1100 m a.s.l.; 12 May 2023; W. Opdekamp leg.; WOR, B028. Description Male Length. Body 12–13.5 mm, wing 11.5–12 mm. head. Face slightly protruding downwards, bare, with facial tubercle, black, shiny except grey pruinose narrow strip along parafacia, on genae and a broad weakly delimited band directly below lunule. Parafacia black, broad, almost as wide as postpedicel, slightly pruinose, long white pilose. Frontal triangle black, shiny, except narrowly pruinose along eye margins and along face, long white pilose, with medial frontal sulcus. Length of eye contiguity about as long or slightly shorter than the length of frons.Angleofapproximationofeyes80–90°.Verticaltriangleblack,pruinose;ocellartriangleshiny and long yellow pilose. Occiput pruinose, yellow pilose. Lunule dark orange, with distinct medial arm, separating acetabula. Scape blackish, anteriorly with setae, inner setae yellow, outer setae black; pedicel blackish, becoming orange on outer third, anteriorly with black setae and yellow pile; postpedicel orange, sometimes darkened in dorsal outer corner, about as high as wide, rounded, pruinose; arista black, sometimes orange apically, almost bare. Eye long white pilose. thorax.Scutumblack,finelypunctured,withlongerectyellowororangepile,shinyexceptanteriorly narrowly pruinose and notopleuron slightly pruinose. Scutellum black, shiny, with long and short erect golden yellow pile, posterior margin without setae. Pleura black, pruinose, with yellow white pile; katepisternum continuously pilose. Haltere pedicellum yellow, capitulum dark brown or black. Wing. Wing including alula entirely microtrichose, veins on outer two third of wing darkened dark brown (most so at veins m-cu, M4 base, r-m, R2+3, R4+5 and M2), inner angle between veins M1 and R4+5 equal to 90°,wingveinsorangeinthebasalpartandblackintheapicalpartofthewing. Legs. Coxae black, with yellow pile. Trochanters black. Femora black, very apex orange; profemur and mesofemur with yellow pile except ventrally on apical half with black pile; metafemur with yellow anterolateral pile, pile longer than width of metafemur, ventrally with scattered long yellow pile and short semi-adpressed mixed yellow and black setae, towards apex setae exclusively black. Tibiae yellow with vague black ring or smudge below middle; tibiae with yellow pile, sometimes mixed with black pile. Tarsi with mixed yellow and black pile; black, except ventrally orange on basal four tarsomeres and sometimes basal two tarsomeres of mesotibia dark orange dorsally. a bdomen . Pile on terga I–IV long and erect, terga I–II with mainly yellow pile, terga III–IV with mainly black pile, tergum II in posterolateral corner with variable small black pile and posteriorly in center with BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 51 mixed black and yellow pile; tergum IV sometimes with a narrow band of yellow pile on anterior margin. Tergum I pruinose, tergum II pruinose in center and anteriorly, terga III–IV shiny. Sterna I–II with long erect golden pile, sterna III–IV with long erect black pile, shorter and adpressed in central part; sternum I pruinose; sternum II shiny but pruinose anteriorly and laterally, sternum III shiny and sternum IV shiny but pruinose posteriorly. Genitalia with surstylus about 2,9 times as long as wide (Fig. 24D); ventral lobe of postgonite more than twice as long as dorsal lobe of postgonite (Fig. 24C); sclerite of the distiphallus with two ventral spurs. Female Length. Body 11.5–13.5 mm, wing 11 mm. Similar to the male, except for normal sexual dimorphism and the following characters. Face more extensively pruinose. Frons shiny, except a narrow strip along eye margin in anterior part. Lunule yellow. Scape, pedicel and postpedicel bright orange. Postpedicel larger than in the male. Capitulum of haltere orange. Pile on the central part of tergum II adpressed. Tergum V shiny, with long erect black pile. Sternum V with long erect black pile, shiny with pruinose posterior margin. Fig. 23. Cheilosia (Montanocheila) contrasta sp. nov. A–B. Holotype, ♂ (ZFMK, ZFMKDIP-00066187); habitus, lateral and dorsal views; body length 12.1 mm. C–D.Paratype,♀(SBA,CNC databasing S Bot 917); habitus, lateral and dorsal views; body length 12.9 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 52 Genetics All DNA barcodes of C. contrasta sp. nov. group together without high support (BS < 90%). Distribution So far only known from the type locations in the Greater and Lesser Caucasus in Armenia and Georgia. Fig. 24. Cheilosia (Montanocheila) contrasta sp. nov. A.Paratype,♂(SBA,CNCdatabasingSBot649); head, lateral view; eye width 1.4 mm. B.Paratype,♀(SBA,CNCdatabasingSBot917);head,lateral view; eye width 1.4 mm. C–D.Paratype,♂(SBA,SB.003117).C. Postgonite, lateral view. D. Surstylus, lateral view. Scale bars: A–B not to scale; C–D in µm. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 53 Biology Collected on forest clearings and on alpine meadows in mountains between 615 and 2601 m a.s.l. Males have been seen hovering in small groups at 1.5 m in the shelter of the last trees near a glacier, in forest clearings near the treeline, at the treeline and 0.5 m above the ground in wind-sheltered hollows along asmallmountainstream.MalesandfemalesvisitflowersofSalix sp. Females have been observed to crawl on and underneath Heracleum sp. leaf rozettes which may indicate that they oviposit here, and that larvae are associated with this plant. Cheilosia (Convocheila) cumanica Szilády, 1938 Fig. 25 Cheilosia cumanica Szilády, 1938: 143. Cheilosia verae Stackelberg, 1968: 229. Syn. with Cheilosia cumanicabyBrădescu(1991). Cheilosia verae – Stackelberg & Richter 1968: 249. — Stackelberg 1970: 62. — Peck 1988: 119. — Barkalov 1993: 712. — Barkalov & Mutin 2018: 484. Cheilosia verae Stackelberg, 1956 [sic] – Gujabidze 2002: 246. Cheilosia cumanica – Mengual et al. 2020: 22. Fig. 25. Cheilosia (Convocheila) cumanica Szilády, 1938. Collected in Georgia. A.♂(SBA,SB.002275); habitus, lateral view; body length 8.4 mm. B.♂(SBA,SB.002284);head,lateralview;eyewidth 1.3 mm. C.♂(SBA,SB.002271);habitus,dorsalview;bodylength8.4mm.D.♀(SBA,SB.002299); head, lateral view; eye width 1.1 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 54 Differential diagnosis Cheilosia cumanica belongs to the subgenus Convocheila Barkalov, 2002. One of the distinctive characters of the subgenus is the pilosity on the face: long pilose along paraface in dorsal one third of face. In the males of Convocheila the ventral lobe of the postgonite is sickle-shaped. Within the Caucasus, the only other member of the subgenus Convocheila is C. laticornis, and the male of C. cumanica can be easily distinguished from C. laticornis by the pilose eye (bare in C. laticornis), the female has few long black pile on the occiput, besides long yellow pile (with only long yellow pile in C. laticornis) and scutellum on posterior margin with robust black setae (with weak, yellow setae in C. laticornis). The male genitalia of C. cumanicaarefiguredinRadenkovićet al. (2020). Material examined Collected in 2018, 2019, 2021, 2022 and 2023; see Mengual et al. (2020) for detailed records from 2018. Genetics All DNA barcodes of C. cumanica are recovered together with high support value (BS = 100%). Remarks In the Caucasus, this taxon is often reported under the name C. verae,butBrădescu(1991)synonymized C. verae under C. cumanica. Our genetic results (Supp.file1: Fig. S1) support this synonymy as specimens from the Caucasus cluster together with specimens from Serbia. Biology During our expeditions, collected between 2 May and 19 July at an altitude between 625 and 2700 m a.s.l. Mostcommononalpinemeadowswhereitfeedsontheflowersofherbaceousplants. Distribution Balkan Peninsula, Carpathian Mountains, Iran, and Caucasus (Armenia, Georgia, Russia). Cheilosia (Cheilosia) cynocephala Loew, 1840 Fig. 26 Chilosia cynocephala Loew, 1840: 32. Differential diagnosis Cheilosia cynocephala is especially similar to C. confusa sp. nov. and C. vernalis. It has a blue body shine; in contrast, in C. confusa and C. vernalis the body shine is black or brown. Usually, the female of C. cynocephala has faint, blackish cloud in the wing (but this characteristics is missing in the only Caucasian studied specimen), missing in the other two species. Another character to exclude C. confusa is the predominantly black pile on the scutum (predominantly yellow pilose in C. confusa). Other characters to exclude C. vernalis are: parafacia wide and pruinose in C. cynocephala (narrower and shiny in C. vernalis), scutum covered largely with black pile (in C. vernalis pile varying from yellow to black) and tarsus of mesoleg black (in C. vernalis often basal two tarsomeres orange). Material examined GEORGIA – Samtskhe-Javakheti•1♀;Borjomi;41.838° N, 43.337° E; 910 m a.s.l.; 2 Sep. 2019; J. Mortelmans leg.; FMT. Genetics All DNA barcodes of C. cynocephala (from Finland and Spain; see Ballester-Torres et al. 2024) are recovered together with low support value (BS < 90%). BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 55 Remarks ReportedfromtheCaucasusforthefirsttime. Distribution Europe, Western Siberia and Caucasus (Georgia). Fig. 26. Cheilosia (Cheilosia) cynocephala Loew, 1840. A.♂(SBA,SB.004468);habitus,lateralview; collected in Altai Republic, Russia; body length 9.9 mm. B.♂(FMT);habitus,dorsalview;collected in Belgium; body length 8.7 mm. C.♀(FMT);habitus,lateralview;collectedinGeorgia;bodylength 8.3 mm. D.♀(FMT);habitus,dorsalview;collectedinGeorgia;bodylength8.3mm.E.♂(FMB); head, lateral view; collected in Belgium; eye width 1.3 mm. F.♀(FMT);head,lateralview;collected in Georgia; eye width 1.2 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 56 Cheilosia (Cheilosia) flavipes (Panzer, 1798) Fig. 27 Syrphus flavipes Panzer, 1797: 10. Cheilosia flavipes – Stackelberg & Richter 1968: 245. — Peck 1988: 102. — Barkalov 1993: 705. — Barkalov & Mutin 2018: 483. — Mengual et al. 2020: 16. Differential diagnosis The male of Cheilosia flavipes has the combination of a bare eye, bare face, bicoloured legs, posterior margin of scutellum without setae and dorsal and ventral pile patches on katepisternum widely separated. These characters are shared with males of C. brunnipennis, C. megaclama sp. nov. and C. nebulosa. It has the basal three or four tarsomeres of the protarsus yellow (black in C. megaclama), arista black (with orange base in C. nebulosa), postpedicel ca 1.5 times as wide as high (ca two times as wide as high in C. brunnipennis)andangleofapproximationofeyeslessthan90°(100–110°inC. brunnipennis). Within the Caucasus, the female C. flavipesiseasilyidentifiedbythecombinationofabareeyeandyellow femora. Fig. 27. Cheilosia (Cheilosia) flavipes (Panzer, 1798). A.♂(SBA);habitus,lateralview;collectedin France; body length 11.1 mm. B.♂(JMG);head,lateralview;collectedinBelgium;eyewidth1.5mm. C.♂(JMG);habitus,dorsalview;collectedinBelgium;bodylength10.7mm.D.♀(SBA,SB.004469); head, lateral view; collected in Belgium; eye width 1.3 mm. Not to scale. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 57 Material examined Species not collected. Genetics All DNA barcodes of C. flavipes (all from Europe) are recovered together with high support value (BS = 100%). Distribution Western and Central Palaearctic, into Siberia. Within the Caucasus only reported from the Armenian Highlands. Fig. 28. Cheilosia (Eucartosyrphus) flavissima Becker, 1894. Collected in Finland. A.♂(SBA, SB.004470); habitus, lateral view; body length 8.0 mm. B.♀(SBA,SB.004473);head,lateralview; eye width 1.2 mm. C.♂(SBA,SB.004471);habitus,dorsalview;bodylength8.1mm.D.♂(SBA, SB.004472); head, lateral view; eye width 1.2 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 64 Biology During our expeditions, collected between 9 May and 13 July at an altitude between 1090 and 2807 m a.s.l. in montane, subalpine and alpine meadows. Distribution Palaearctic. Within the Caucasus known from Armenia, Georgia and Russia. Cheilosia (Montanocheila) gorodkovi Stackelberg, 1963 Fig. 32 Cheilosia gorodkovi Stackelberg, 1963: 518. Cheilosia kuznetzovae Skufjin, 1977: 58. Syn. with Cheilosia gorodkovi by Barkalov & Mutin (2018). Differential diagnosis As a member of the subgenus Montanocheila, males of Cheilosia gorodkovicanbeidentifiedfromthose of all other subgenera by the apical sclerite of distiphallus, having two pairs (anterior and posterior) of lobes. Within the subgenus, it is similar to Cheilosia rufa sp. nov. For differences with that species, see Differential diagnosis under Cheilosia rufa. Femalescanbemoredifficulttoidentifyasamemberof the subgenus Montanocheila given that the often-used character to do so, wing with brown pattern in the middle, is not always obvious in C. gorodkovi. However, it is still possible to separate it from similar looking females from other subgenera occurring in the Caucasus by the black femora with yellow apex (femora all yellow in C. albipila and C. aurantia sp. nov.). Within the subgenus Montanocheila occurring in the Caucasus, C. gorodkovi has a not protruding face (Fig. 32F) (protruding in the other species), short pile on scutellum (shorter than diameter of metafemur, longer than diameter of metafemur in the other species), metafemur anteroventrally with pile shorter than diameter of metafemur (longer than diameter of metafemur in the other species) and on average with shorter body length (on average 9.5 mm vs usually larger than 9.5 mm in other Montanocheila). The male genitalia of C. gorodkoviarefiguredin Claussen (1998). Material examined Cheilosia gorodkovi was collected in 2018, 2019, 2022 and 2023, but 2018 records not published in Mengual et al. (2020); hence, all records are reported here. ARMENIA – Kotayk Province•1♀;Tsaghkadzorarea,towardsGrandPalaceHotel;40.53310°N, 44.69966°E;1975ma.s.l.;24May2022;X.Mengualleg.;ZFMK,ZFMK-DIP-00093688=ZFMKTIS-8014644. GEORGIA – Mtskheta-Mtianeti•10♂♂,2♀♀;Lutkhubi;42.3867°N,44.79°E;1580ma.s.l.;6May 2023;F.VandeMeutterleg.;FMT•5♂♂1♀;Lutkhubi;42.3951°N,44.7847°E;2138ma.s.l.;6May 2023;F.VandeMeutterleg.;FMT•2♂♂;samedataasforpreceding;ZFMK•2♂♂;Lutkhubi; 42.3984°N,44.7866°E;2180ma.s.l.;6May2023;W.Opdekampleg.;WOR,C003,C005•14♂♂; Lutkhubi;42.3823°N,44.7856°E;1500ma.s.l.;6May2023;W.Opdekampleg.;WOR,D011, D013,D014,D020,D021,D023toD027,D029,D031,D034,D039•6♂♂;Lutkhubi;42.3938°N, 44.7857°E;2120ma.s.l.;6May2023;W.Opdekampleg.;WOR,E001,E009toE011,E013,E015 •1♂;Lutkhubi;42.3930°N,44.7929°E;1734ma.s.l.;8May2023;W.Opdekampleg.;WOR, C004•1intersex;Lutkhubi;42.3989°N,44.7995°E;2100ma.s.l.;8May2023;W.Opdekampleg.; WOR,D003•3♂♂;Lutkhubi;42.3984°N,44.7996°E;2068ma.s.l.;8May2023;S.Botleg.;SBA, SB.002356=ZFMK-TIS-8027993,SB.002339=ZFMK-TIS-8028447,ZFMK-TIS-8028448•1♀; samedataasforpreceding;SBA,ZFMK-TIS-8027994•9♂♂,1♀;Lutkhubi;42.3936°N,44.7923°E; 1760 m a.s.l.; 8 May 2023; F. Van de Meutter leg.; FMT. – Samegrelo-Zemo Svaneti•1♂;Sof BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 65 Ushguli;42.888°N,42.978°E;2900ma.s.l.;28Jun.2018;S.Botleg.;CNC,CNCdatabasingS.Bot 750•1♀;42.9062°N,42.9370°E;2615ma.s.l.;16Jun.2019;F.VandeMeutterleg.;FMT,ZFMKTIS-8009614•1♂;Ushguli;42.900°N,42.934°E;2700ma.s.l.;17Jun.2019;S.Botleg.;SBA,CNC databasing S. Bot 923 = SB.002338. – Samtskhe-Javakheti•1♀;Kodiani;41.7305°N,43.3537°E; 2160ma.s.l.;10May2023;F.VandeMeutterleg.;FMT,ZFMK-TIS-8027946•2♀♀;Kodiani; 41.7268°N,43.3490°E;2150ma.s.l.;10May2023;W.Opdekampleg.;WOR,B004,B006. Fig. 32. Cheilosia (Montanocheila) gorodkovi Stackelberg, 1963. Collected in Georgia. A.♂(SBA,CNC databasing S. Bot 750); habitus, lateral view; body length 9.0 mm. B.♀(FMT,ZFMK-TIS-8009614); habitus, dorsal view; body length 9.1 mm. C.♂(SBA,SB.002339);habitus,dorsalview;bodylength 10.9 mm. D.♀(FMT,ZFMK-TIS-8009614);habitus,lateralview;bodylength9.1mm.E.♂(SBA,CNC databasing S. Bot 750); head, lateral view; eye width 1.5 mm. F.♀(SBA,FMT,ZFMK-TIS-8009614); head, lateral view; eye width 1.3 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 66 Genetics All DNA sequences of C. gorodkovi group together with high support (BS = 98.9%). Remarks Stackelberg (1963) described this species from East-Siberia (Irkutsk Region) and Barkalov & Mutin (2018) synonymized Cheilosia kuznetzovae Skufjin, 1977 with it after studying the types, also reporting the species from European parts of Russia, Siberia and northern Far East. Reported from the Caucasus forthefirsttime.WecomparedthespecimensoftheCaucasuswithtwomalescollectedinSiberia,and found them to be morphologically identical, including genitalia. Biology During our expeditions, collected between 6 May and 28 June at an altitude between 1500 and 2900 m a.s.l. on open subalpine and alpine meadows. Males hover in groups at tree tops, or at protruding ridgesonthemountainslope.Visitsavarietyofmainlylowflowers,includingRanunculus sp. and white and yellow crucifers. Distribution Europe (Poland and European parts of Russia), Caucasus (Armenia and Georgia), east through Siberia up to the Far East (Magadan Region, Yakutia). Cheilosia (Cheilosia) grossa (Fallén, 1817) Fig. 33 Eristalis grossa Fallén, 1817: 53. Cheilosia grossa Meigen, 1822 [sic] – Gujabidze 2002: 246. Cheilosia grossa – Barkalov 1993: 718. — Mengual et al. 2020: 17. Differential diagnosis Cheilosia grossa is a large species (11–12 mm) with dense body pile, pilose eye, bare face, bicoloured legsandposteriormarginofscutellumwithoutsetae.Identifiedfromotherspeciesoccurringinthe Caucasus having this set of characters except C. balu by the black postpedicel (at least basoventrally orange in the others). Easily distinguished from C. balu by the yellow metafemur (with black ring in C. balu), black pile on eye (brown or yellow in C. balu; Fig. 11B, D), scutum with yellow pile (in the male of C. baluwithblackpile,inthefemalewithfieldofblackpileinposteriorpart)and pruinose sterna (predominantly shiny in C. balu). Very similar to C. pseudogrossa, but face bare (pilose in C. pseudogrossa). For more differences, see at the Differential diagnosis of C. pseudogrossa. Material examined Not collected in 2018, but collected in 2023. GEORGIA – Samtskhe-Javakheti•2♀♀;Sakire;41.7301°N,43.3306°E;1820ma.s.l.;10May2023; F. Van de Meutter leg.; FMT, ZFMK-TIS-8027941. Genetics In our NJ tree we recover a cluster of three species with high support (BS = 100%), C. albipila, C. grossa and C. pseudogrossa. The two DNA sequences of C. pseudogrossa group together with high support (BS = 99.7%), as well as the barcodes of C. grossa (BS = 100%), except for three (Scandinavian) sequences that are placed within the C. albipila cluster. The study of the available photographs in BOLD of those three specimens of C. grossa (KWi-089, KWi-090 and NORSY471) do not question their identification. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 67 Distribution PalaearcticandUttahPradeshinnorthernIndia.WithintheCaucasusreportedfromGeorgiaforthefirst time. Cheilosia (Cheilosia) himantopus (Panzer, 1798) Fig. 34 Syrphus himantopus Panzer, 1797: 9. Differential diagnosis Cheilosia himantopus is very similar to C. canicularis,butitfliesinspringratherthaninsummer.For morphological differences, see the Differential diagnosis under C. canicularis. Similar to C. orthotricha, whichonaveragefliesearlierinspring.C. himantopus differs from C. orthotricha by having ventral half Fig. 33. Cheilosia (Cheilosia) grossa (Fallén, 1817). A.♂(SBA,SB.004478);habitus,dorsalview; collected in the Netherlands; body length 13.0 mm. B.♂(SBA,SB.004478);head,lateralview;collected in the Netherlands; eye width 1.6 mm. C.♂(SBA,SB.004479);habitus,lateralview;collectedinthe Netherlands; body length 14.7 mm. D.♀(FMT);head,lateralview;collectedinGeorgia;eyewidth 1.5 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 68 of eye bare (at most ventral one third bare in C. orthotricha), pile on posterior anepisternum with wavy apex (with straight apex in C. orthotricha) and face slightly pruinose (shiny in C. orthotricha). Material examined Cheilosia himantopus was not collected in 2018, but collected in 2019 and 2022. GEORGIA – Imereti•1♂;Abastumani,roadAbastumanitoSairme;41.8242°N,42.8472°E; 2150 m a.s.l.; 10 Jun. 2019; F. Van de Meutter leg.; FMT. – Kakheti•1♀;Kobadze;41.861393°N, 45.301954°E;1430ma.s.l.;1Jun.2022;X.Mengualleg.;ZFMK,ZFMK-DIP-00094142=ZFMKTIS-8014588. – Samtskhe-Javakheti•1♀;roadfromSakiretoTsikhisjvari;41.7250°N,43.3606°E; 2519ma.s.l.;9Jun.2019;F.VandeMeutterleg.;FMT•1♂;BorjomiN.P.;41.7280°N,43.3640°E; 2327ma.s.l.;9Jun.2019;L.Hofsteeleg.;LHH•2♀♀;roadfromSakiretoTsikhisjvari;41.7251°N, 43.3605°E;2519ma.s.l.;9Jun.2019;X.Mengualleg.;ZFMK,ZFMK-DIP-00066518=ZFMKFig. 34. Cheilosia (Cheilosia) himantopus (Panzer, 1798). Collected in Georgia. A.♂(LHH);habitus, lateral view; body length 14.4 mm. B.♂(LHH);head,lateralview;eyewidth1.7mm.C.♂(LHH); habitus, dorsal view; body length 14.7 mm. D.♀(SBA,SB.002961);head,lateralview;eyewidth 1.7 mm. Not to scale. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 69 TIS-8008823,ZFMK-DIP-00066519 = ZFMK-TIS-8008824• 1 ♀;Borjomi N.P.;41.8210° N, 42.8340°E;1992ma.s.l.;11Jun.2019;S.Botleg.;SBA,SB.002961•3♀♀;Abastumani;41.79°N, 42.82°E;1515ma.s.l.;11Jun.2019;J.vanSteenisleg.;JSB,2019-00.800to2019-00.802 Genetics In our NJ tree we recover a cluster (BS = 99.8%) with the barcodes of C. himantopus and the sequences of C. canicularis. Although certain structure can be seen in the arrangement of the molecular data, both species cannot be distinguished unmistakenly with DNA barcodes. Remarks ReportedfromtheCaucasusforthefirsttime.Maybethespecieswasoverlookedbeforegiventhat severalreferencesfortheCaucasuspredateStuke&Claussen(2000)inwhichtheidentificationand status of C. himantopuswereclarified. Biology During our expeditions, collected between 1 June and 11 June at an altitude between 1430 and 2519 m a.s.l. Distribution Europe, Caucasus (Georgia). Cheilosia (Floccocheila) illustrata portschinskiana Stackelberg, 1960 Fig. 35 Cheilosia portschinskiana Stackelberg, 1960: 441. Cheilosia oestracea (Linnaeus, 1761) [sic] var. b, c, d, e, f – Portschinsky 1877: 161. Cheilosia oestracea (Linnaeus, 1758) – Radde 1899: 453. Cheilosia portschinskiana – Stackelberg & Richter 1968: 248. — Stackelberg 1970: 61. Cheilosia illustrata portschinskiana – Peck 1988: 105. — Barkalov 1993: 718. — Claussen 1998: 385; Barkalov & Mutin 2018: 485. — Mengual et al. 2020: 23. Cheilosia portschinskiana Stackelberg, 1956 [sic] – Gujabidze 2002: 246. Cheilosia oestracae (Linnaeus, 1758) [sic] – Gujabidze 2002: 246. Differential diagnosis Cheilosia illustrata portschinskianaisaverydistinctivespecies,easilyidentifiedfromotherspeciesof Cheilosia in the Caucasus by the combination of dense body pile, pilose eye, bare face, posterior margin of scutellum without setae and alternating pattern on body of black and pale (white and/or yellow and/or orange) pile bands (Fig. 35A, C). Very similar to extralimital nominal C. illustrata, but face bare (almost always pilose in nominal C. illustrata) and postpedicel regularly orange to some extent (usually black or dark brown in nominal C. illustrata, but much overlap). In some specimens in the Caucasus, all pile on tergum II black instead of whitish. Material examined Collected in 2018, 2019, 2021 and 2022, see Mengual et al. (2020) for detailed records from 2018. Genetics All DNA barcodes of C. illustrata illustrata from Europe and C. illustrata portschinskiana from the Caucasus cluster together with high support (BS = 100%). The single DNA barcode of Cheilosia European Journal of Taxonomy 1023: 1–181 (2025) 70 motodomariensis Matsumura, 1916 from Russian Far East in our dataset is resolved embedded within the cluster of C. illustrata. Remarks ThistaxonwasfirstdescribedasanewspeciesbyStackelberg(1960).ItisverysimilartoC. illustrata (Harris, 1779) and therefore regarded as a subspecies of C. illustrata since Barkalov (1981). According to Barkalov (1993), C. illustrata portschinskiana is the only subspecies of C. illustrata occurring in the Caucasus.Ourgeneticresearchconfirmsthecloserelationshipwith C. illustrata and C. motodomariensis, since they are genetically indistinguishable (Supp.file1: Fig. S1). Biology During our expeditions, collected between 18 June and 3 August at an altitude between 1476 and 2900ma.s.l.aswellasonherbaceousflowersasonfloweringtrees(Sorbus sp.). Fig. 35. Cheilosia (Floccocheila) illustrata portschinskiana Stackelberg, 1960. Collected in Georgia. A.♂(SBA,SB.002354);habitus,lateralview;bodylength12.7mm.B.♂(SBA,SB.002352);head, lateral view; eye width 1.6 mm. C.♂(SBA,SB.002352);habitus,dorsalview;bodylength15.5mm. D.♀(SBA,SB.002373);head,lateralview;eyewidth1.6mm.Nottoscale. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 71 Distribution Caucasus (Armenia, Georgia, Russia). Cheilosia (Cheilosia) inarmata sp. nov. urn:lsid:zoobank.org:act:EB32D55D-8523-49C6-B67E-5C8DE02A0455 Figs 36–37 Cheilosia impressa Loew, 1840 – Stackelberg & Richter 1968: 246 (Caucasian records). — Stackelberg 1970: 61 (Caucasian records). — Peck 1988: 105 (Caucasian records). — Barkalov 1993: 724 (Caucasian records). — Mengual et al. 2020: 17. — Speight 2020a: 37 (Caucasian records). Cheilosia impressa Loew, 1848 [sic] – Gujabidze 2002: 245. Differential diagnosis Cheilosia inarmata sp. nov. is similar to C. impressa Loew, 1840 and C. schnabli, but these two species are unique among all European Cheilosia in possessing a distinct, knob-like basolateral projection on the externalsurfaceoftheprocoxae(Fig.37C)(Vujićet al. 1998; Speight 2020a). This diagnostic projection is absent in C. inarmata (Fig. 37B). Given the large morphological variation within both C. inarmata and C. impressa, other differences between C. inarmata and C. impressa could not be found, except for the frontal triangle in the male usually pruinose in our new species (male frontal triangle usually shiny in C. impressa). Besides the absence of the projection on the fore coxa, differences with C. schnabli include the rough and densely punctured scutum in C. inarmata (in C. schnablithescutumisfinelypunctured), tergum III in male with a dull area in anterior half never reaching the posterior margin (in C. schnabli male tergum III with dull area extending to posterior margin), and the dorsal lobe of postgonite of the male genitalia broadened below apex (Fig. 37F) and sclerite of the distiphallus asymmetric (Fig. 37E, dorsal lobe of postgonite narrow and elongated in apical part and sclerite of the distiphallus symmetric in C. schnabli). Females of C. inarmata have a short and adpressed pile on scutum, while females of C. schnabli have a semi-adpressed short pile mixed with some longer pile on scutum. Etymology ThespeciesnamederivesfromtheLatinprefix‘in-’ meaning ‘without’ (Brown 1956: 436) and the Latin word ‘armatus’ meaning ‘furnished with weapons’ (Brown 1956: 806), and it refers to the lack of a knoblike projection on the fore coxae. Species epithet is to be treated as an adjective. Material examined Holotype GEORGIA•♂;Samtskhe-Javakheti,41.8234°N,42.8400°E;2025ma.s.l.;11Jun.2019;X.Mengual leg.; ZFMK, ZFMK-DIP-00066425 = ZFMK-TIS-8008794. Paratypes GEORGIA – Adjara Region•1♀;KintrishiNatureReserve;41.7553°N,42.1129°E;2280ma.s.l.; 14–28Jul.2018;GGBC-membersleg.;ZFMK,ZFMK-TIS-8010475•1♂;KintrishiNatureReserve; 41.7344°N,41.9888°E;458ma.s.l.;20Jul.2018;X.Mengualleg.;ZFMK,ZFMK-DIP-00053910= ZFMK-TIS-8005513•1♀;samedataasforpreceding;ZFMK,ZFMK-DIP-00053911=ZFMKTIS-8005520•1♀;MtiralaNationalPark,MountMtirala;41.7990°N,41.6576°E;1318ma.s.l.;25Jul. 2018; A. Reimann leg.; MTD, Dip-AR-4545 = ZFMK-TIS-8002677. – Imereti•1♀;roadfrom AbastumanitoSairme;41.86433°N,42,77842°E;1830ma.s.l.;10Jun.2019;X.Mengualleg.;ZFMK, ZFMK-DIP-00066415. – Kakheti•2♂♂;LagodekhiN.P.;41.8635°N,46.3412°E;1851ma.s.l.;2Jul. 2021;S.Botleg.;SBA,SB.003170,SB.003171•2♀♀;samedataasforpreceding;SBA,SB.003172, SB.003173•1♀;samedataasforpreceding;ZFMK,ZFMK-TIS-8011515•1♀;LagodekhiN.P.; 41.877°N,46.384°E;2652ma.s.l.;3Jul.2021;S.Botleg.;SBA,SB.003169•2♀♀;LagodekhiN.P.; European Journal of Taxonomy 1023: 1–181 (2025) 72 41.9032°N,46.3876°E;2807ma.s.l.;4Jul.2021;S.Botleg.;SBA,SB.003167,SB.003168.– Mtskheta-Mtianeti•2♀♀;Stepantsminda;42.6591°N,44.6366°E; 1740–2500 m a.s.l.; 3 Aug. 2001; J.-H.Stukeleg.;ZFMK,ZFMK-DIP-00058257,ZFMK-DIP-00058258•1♂,1♀;Kazbeg,Dzhuta; 42.564°N,44.735°E;2183ma.s.l.;11Jul.2012;Th.Zeegersleg.;GPA•2♀♀;TbilisiNationalPark; 41.879°N,45.016°E;22Jun.2019;1251ma.s.l.;S.Botleg.;SBA,SB.003175,SB.003176•1♀; TbilisiN.P.;41.8808°N,45.0203°E;1270ma.s.l.;22Jun.2019;X.Mengualleg.;ZFMK,ZFMKDIP-00066405=ZFMK-TIS-8008785•1♂;Stepantsminda;42.6722°N,44.6113°E;2070ma.s.l.; 4Jul.2019;A.Reimannleg.;MTD,ZFMK-TIS-8002827•1♀;samedataasforpreceding;MTD,DipAR-5259=ZFMK-TIS-8002826•1♀;Stepantsminda;44,6492°N,42.6546°E;1825ma.s.l.;6–12Jul. 2019;A.Ssymankleg.;Malaisetrap;ASW,ZFMK-DIP-00069439=ZFMK-TIS-8009526•1♀;Gveleti, roadtowaterfall;44.6200°N,42.7053°E;1560ma.s.l.;6Jul.2019;A.Reimannleg.;MTD,DipAR-4749=ZFMK-TIS-8002801•1♂;Juta,42.5794°N,44.7433°E;2150ma.s.l.;10Jul.2019; A.Ssymankleg.;ASW•1♂;Stepantsminda;42.7047°N,44.6210°E;1540ma.s.l.;12Jul.2019; A.Ssymankleg.;ASW,Ssy9506-03=ZFMK-TIS-8009417•3♂♂;Gergeti;42.6669°N,44.6127°E; 2175ma.s.l.;13Jul.2019;A.Ssymankleg.;ASW•1♀;Gergeti;42.6616°N,44.6155°E;2080ma.s.l.; 13Jul.2019;A.Ssymankleg.;ASW•1♀;Stepantsminda;42.6577°N,44.6568°E;1950ma.s.l.; 17Jul.2019;A.Ssymankleg.;ASW,Ssy9523-02=ZFMK-TIS-8009418;ASW•1♀;TbilisiN.P.; 41.880°N,45.023°E;1289ma.s.l.;4May2023;S.Botleg.;SBA,SB.003157•2♂♂,1♀;TbilisiN.P.; 41.877°N,45.0138°E;1250ma.s.l.;4May2023;F.VandeMeutterleg.;FMT•1♂;Kithoki; 42.4147°N,44.7549°E;1240ma.s.l.;8May2023;F.VandeMeutterleg.;FMT•2♀♀;TbilisiN.P.; 41.8770°N,45.0137°E;1248ma.s.l.;9May2023;S.Botleg.;SBA,SB.003158,SB.003159.–RachaLechkhumi and Kvemo Svaneti•4♂♂;Tsana;42.909°N,43.142°E;1900ma.s.l.;29Jun.2018; S.Botleg.;SBA,SB.003199toSB.003202•1♂;Zeskho;42.888°N,43.233°E;1900ma.s.l.;30Jun. 2018,S.Botleg.;SBA,SB.003195•2♀♀;samedataasforpreceding;SBA,SB.003196,SB.003197• 1♂;Zeskho;42.888°N,43.233°E;1900ma.s.l.;1Jul.2018;S.Botleg.;SBA,SB.003193•1♀;same dataasforpreceding;SBA,SB.003194•1♂;Tsana;42.90°N,43.14°E;1830ma.s.l.;18Jun.2019; J.vanSteenisleg.;JSB,2019-01.061•2♂♂;Tsana;42.8887°N,43.1429°E;1757ma.s.l.;18Jun. 2019;X.Mengualleg.;ZFMK,ZFMK-DIP-00066432,ZFMK-DIP-00066440•1♂;Tsana;42.915°N, 43.143°E;1969ma.s.l.;19Jun.2019;S.Botleg.;SBA,SB.003178•1♀;samedataasforpreceding; SBA,SB.003177•1♂;samedataasforpreceding;L.Hofsteeleg.;LHH•6♂♂;Tsana;42.916°N, 43.142°E;1975ma.s.l.;19Jun.2019;X.Mengualleg.;ZFMK,ZFMK-DIP-00066428,ZFMKDIP-00066429 = ZFMK-TIS-8008795, ZFMK-DIP-00066430, ZFMK-DIP-00066431, ZFMKDIP-00069433=ZFMK-TIS-8009513,ZFMK-DIP-00066436•3♀♀;samedataasforpreceding; ZFMK,ZFMK-DIP-00066416,ZFMK-DIP-00066438,ZFMK-DIP-00069441=ZFMK-TIS-8009511• 2♂♂;Tsana;42.8862°N,43.1563°E;2252ma.s.l.;19Jun.2019;J.H.Skevingtonleg.;CNC, CNC1386850,CNC1386878•1♀;samedataasforpreceding;CNC,CNC1386883•1♀;42.82111°N, 43.16069°E;1450ma.s.l.;20Jun.2019;X.Mengualleg.;ZFMK,ZFMK-DIP-00066417=ZFMKTIS-8008789•1♀;nearAdishi;42.9986°N,42.9088°E; 2140 m a.s.l.; 11 Sep. 2019; J. Mortelmans leg.;FMT•1♂;aboveGlola;42.668°N,43.630°E;2598ma.s.l.;9Jul.2021;S.Botleg.;SBA, SB.003160•1♂;samedataasforpreceding;XLS,SB.003161•1♀;samedataasforpreceding; ZFMK, ZFMK-TIS-8011487. – Samegrelo-Zemo Svaneti•1♂;Mestia;43.080°N,42.762°E; 1800ma.s.l.;22Jun.2018;S.Botleg.;SBA,SB.003214•2♀♀;Ushguli;42.914°N,43.010°E; 2100ma.s.l.;23Jun.2018;S.Botleg.;SBA,SB.003212,SB.003213•1♂;Ushguli;42.950°N, 43.075°E;2275ma.s.l.;24Jun.2018;S.Botleg.;SBA,SB.003209•2♀♀;samedataasforpreceding; SBA,SB.003210,SB.003211•1♂;42.948°N,43.021°E;2800ma.s.l.;25Jun.2018;S.Botleg.;SBA, SB.003207•1♀;samedataasforpreceding;SBA,SB.003208•2♂♂;42.963°N,42.990°E; 2300ma.s.l.;26Jun.2018;S.Botleg.;SBA,SB.003203,SB.003204•2♀♀;samedataasforpreceding; SBA,SB.003205,SB.003206•1♀;Ushguli;42.916°N,43.018°E;2140ma.s.l.;29Jun.2018;S.Bot leg.;SBA,SB.003198•1♂;Mestia;43.042°N,42.768°E;1473ma.s.l.;13Jun.2019;S.Botleg.; SBA,SB.003182•1♀;Mestia;43.0424°N,42.7681°E;1473ma.s.l.;13Jun.2019;J.H. Skevington leg.;CNC,CNC1386425•2♂♂;42.948°N,43.070°E;2258ma.s.l.;15Jun.2019;S.Botleg.;SBA, BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 73 SB.003180,SB.003181•3♂♂;42.9437°N,43.0539°E;2220ma.s.l.;15Jun.2019;X.Mengualleg.; ZFMK, ZFMK-DIP-00066433, ZFMK-DIP-00066434 = ZFMK-TIS-8008796, ZFMK-DIP-00066441 •1♀;samedataasforpreceding;ZFMK,ZFMK-DIP-00066437•3♂♂;42.9142°N,43.0076°E; 2082m a.s.l.; 15 Jun. 2019; X. Mengual leg.; ZFMK, ZFMK-DIP-00066435, ZFMK-DIP-00066439 = ZFMK-TIS-8008797,ZFMK-DIP-00066442•4♂♂;Ushguli;42.56°N,43.04°E;2260ma.s.l.;15Jun. 2019;J.vanSteenisleg.;JSB,2019-01.043to2019-01.046•1♀;samedataasforpreceding;JSB, 2019-01.047•3♂♂;Ushguli;42.91°N,43.01°E;2100ma.s.l.;15Jun.2019;J.vanSteenisleg.;JSB, 2019-01.048to2019-01.050•2♀♀;samedataasforpreceding;JSB,2019-01.051,2019-01.052•1♂; Ushguli;42.94°N,43.05°E;2220ma.s.l.;15–17Jun.2019;J.vanSteenisleg;Malaisetrap;JSB,201901.058•1♀;samedataasforpreceding;JSB,2019-01.059•1♂;42.9471°N,43.0671°E;2257ma.s.l.; 15Jun.2019;J.H.Skevingtonleg.;CNC,CNC1386559•1♀;Ushguli;42.909°N,43.007°E; 2294ma.s.l.;16Jun.2019;S.Botleg.;SBA,SB.003179•1♂;Ushguli;42.56°N,43.04°E; 2260ma.s.l.;16Jun.2019;J.vanSteenisleg.;JSB,2019-00.908=ZFMK-TIS-8009608•1♀;same dataasforpreceding;JSB,2019-01.055•1♀;Ushguli;42.94°N,43.07°E;2300ma.s.l.;16Jun.2019; J.vanSteenisleg.;JSB,2019-01.056•2♀♀;Ushguli;42.91°N,43.01°E;2135ma.s.l.;16Jun.2019; J.vanSteenisleg.;JSB,2019-01.053,2019-01.054•1♂;Ushguli;42.910°N,43.000°E;2120ma.s.l.; 17Jun.2019;L.Hofsteeleg.;LHH•1♀;nearUshguli,uptotheruins;42.910°N,43.007°E; 2295ma.s.l.;17Jun.2019;X.Mengualleg.;ZFMK,ZFMK-DIP-00066418=ZFMK-TIS-8008790• 1♂;Ushguli;42.91°N,42.93°E;2290ma.s.l.;17Jun.2019;J.vanSteenisleg.;JSB,2019-01.057• 1♂;nearShovi;42.713°N,43.701°E;2022ma.s.l.;7Jul.2021;S.Botleg.;SBA,SB.003166•2♀♀; samedataasforpreceding;SBA,SB.003164,SB.003165•1♂;nearChiora;42.7625°N,43.5540°E; 2027ma.s.l.;8Jul.2021;S.Botleg.;SBA,SB.003162•1♀;samedataasforpreceding;SBA, SB.003163;SBA•2♂♂;42.9125°N,43.0549°E;2299ma.s.l.;11Jul.2021;S.Botleg.;SBA, SB.003152,SB.003153•1♂;samedataasforpreceding;ZFMK,ZFMK-TIS-8011554•1♀;samedata asforpreceding;ZFMK,ZFMK-TIS-8011555•1♀;42.9159°N,43.0191°E;2151ma.s.l.;12Jul. 2021;S.Botleg.;SBA,SB.003154•1♂;42.9616°N,43.0914°E;2447ma.s.l.;12Jul.2021;S.Bot leg.;SBA,SB.003155•2♂♂;42.9091°N,43.0031°E;2166ma.s.l.;13Jul.2021;S.Botleg.;SBA, SB.003149,SB.003150•1♂;samedataasforpreceding;ZFMK,ZFMK-TIS-8011494•1♀;samedata asforpreceding;SBA,SB.003151•1♀;43.0275°N,42.9115°E;2887ma.s.l.;14Jul.2021;S.Bot leg.; SBA, SB.003156. – Samtskhe-Javakheti•1♀;BorjomiN.P.;41.831°N,43.268°E;1780ma.s.l.; 17Jun.2018;S.Botleg.;SBA,SB.003215•2♂♂;BorjomiN.P.;41.824°N,42.848°E;2165ma.s.l.; 10Jun.2019;S.Botleg.;SBA,SB.003187,SB.003188•4♀♀;samedataasforpreceding;SBA, SB.003189toSB.003192•3♂♂,2♀♀;samedataasforpreceding;L.Hofsteeleg.;LHH•4♂♂; BorjomiN.P.;41.86°N,42.77°E;1830ma.s.l.;10Jun.2019;J.vanSteenisleg.;JSB,2019-01.023, 2019-01.027=ZFMK-TIS-8009609,2019-01.028,2019-01.029•3♀♀;samedataasforpreceding; JSB,2019-01.030to2019-01.032•1♀;BorjomiN.P.;41.864°N,42.789°E;1798ma.s.l.;11Jun. 2019;S.Botleg.;SBA,SB.003186•4♂♂;BorjomiN.P.;41.8234°N,42.84°E;2025ma.s.l.;11Jun. 2019; X. Mengual leg.; ZFMK, ZFMK-DIP-00066423 = ZFMK-TIS-8008793, ZFMK-DIP-00066424, ZFMK-DIP-00066426,ZFMK-DIP-00066427•11♀♀;samedataasforpreceding;ZFMK,ZFMKDIP-00066406 = ZFMK-TIS-8008786, ZFMK-DIP-00066409, ZFMK-DIP-00066410 = ZFMKTIS-8008788, ZFMK-DIP-00066411 to ZFMK-DIP-00066414, ZFMK-DIP-00066419, ZFMKDIP-00066420=ZFMK-TIS-8008792, ZFMK-DIP-00066421 •1♂;BorjomiN.P.;41.863°N, 42.789°E;1800ma.s.l.;11Jun.2019;X.Mengualleg.;ZFMK,ZFMK-DIP-00066443=ZFMKTIS-8008798•1♂;BorjomiN.P.;41.82°N,42.84°E;2100ma.s.l.;11Jun.2019;J.vanSteenisleg.; JSB,2019-01.033•6♀♀;samedataasforpreceding;JSB,2019-01.034to2019-01.039•1♀; Abastumani;41.79°N,42.82°E;1515ma.s.l.;11Jun.2019;J.vanSteenisleg.;JSB,2019-01.041• 1♂;BorjomiN.P.;41.8181°N,42.8316°E;2004ma.s.l.;11Jun.2019;J.H.Skevingtonleg.;CNC, CNC1386312•4♀♀;samedataasforpreceding;CNC,CNC1386258,CNC1386259,CNC1386261, CNC1386275•1♂;BorjomiN.P.;41.8224°N,42.8444°E,2098ma.s.l.;11Jun.2019;J.H.Skevington leg.;CNC,CNC1386170•1♀;BorjomiN.P.;41.8697°N,42.7923°E;1683ma.s.l.,11Jun.2019;J.H. Skevingtonleg.;CNC,CNC1386364•2♂♂;BorjomiN.P.;41.823°N,42.841°E;2049ma.s.l.;11Jun. European Journal of Taxonomy 1023: 1–181 (2025) 80 Material examined ARMENIA – Kotayk Province•1♂;Tsaghkadzor,Y.S.U.RestHouse;40.533625°N,44.703028°E; 1915 m a.s.l.; 23 May 2022; X. Mengual leg.; ZFMK, ZFMK-DIP-00093658 = ZFMK-TIS-8014607. GEORGIA – Mtskheta-Mtianeti•1♀;TbilisiN.P.;41.880°N,45.023°E;1289ma.s.l.;4May2023; S. Bot leg.; SBA, SB.002371 = ZFMK-TIS-8028020. Fig. 40. Cheilosia (Cheilosia) latifrons (Zetterstedt, 1843). A–C.♂(ZFMK,ZFMK-TIS-8014607); collected in Armenia; body length 9.2 mm. A. Habitus, lateral view. B. Head, lateral view; eye width 1.3 mm. C. Habitus, dorsal view. D.♀(SBA,ZFMK-TIS-8028020);head,lateralview;collectedin Georgia; eye width 1.1 mm. Not to scale. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 81 Genetics The DNA barcodes of Caucasian specimens cluster together with sequences from Europe with high support (BS = 100%). Remarks Stackelberg & Richter (1968) reported this species as C. intonsa from two localities in Armenia. We are notawareofanyotherpublishedrecordsfromtheCaucasus.Thus,weprovidethefirstrecordofthis speciesforGeorgiaandnewrecordsforArmeniaaftermorethanfivedecades. Biology During our expeditions, collected between 4 May and 23 May at an altitude between 1289 and 1915 m a.s.l. Distribution Palaearctic. Within the Caucasus known from Armenia and Georgia. Cheilosia (Taeniochilosia) longifacies sp. nov. urn:lsid:zoobank.org:act:58001D28-B9E4-4B31-8542-B846D4B3993E Fig. 41 Differential diagnosis Cheilosia longifacies sp. nov. belongs to the caerulescens species group within the subgenus Taeniochilosia. This species group is recognized by typically having bicoloured legs (yellow and black) and infuscate wing cross-veins. The caerulescens species group has recently been revised (Ståhls & Barkalov 2017) and when using their key, C. longifacies keys out to C. circassica, which also occurs in the Caucasus (but is synonymized in this publication with C. armeniaca). Compared to C. armeniaca, C. longifacies has a larger body size (8.5–11 mm vs 8.5–9 mm) and the face further protruding, with the facial tubercle much lower relative to the ventral side of the eye, giving a snout-like appearance (Fig. 41B) (in C. armeniaca the face is less protruding; Fig. 6B), face with lateral stripe less pruinose, parafacia shiny except for the dorsal corners pruinose (in C. armeniaca parafacia has the dorsal half pruinose), eye contiguity ca 0.8 times as long as frons in C. longifacies (ca 0.6 times in C. armeniaca), frontal triangle shiny in C. longifacies instead of pruinose in C. armeniaca, frontal triangle with predominantly erect pile (in C. armeniaca frontal triangle with short erect pile only medially, laterally with dense forwardly directed pile with wavy apex Fig. 6B), dorsal margin of occiput with long yellow pile and some sparse black pile intermixed (only with yellow pile in C. armeniaca Fig. 6B), scutum with black pile intermixed with yellow pile (scutum with yellow pile in C. armeniaca), on body pile wavy apices more pronounced and more commonly occurring in C. armeniaca (e.g., on frons, posterior part of scutum and posterior katepisternum), tibiae with narrower black ring in C. longifacies (Fig. 41A) leaving apex of metafemur distinctly yellow (black ring reaching apex in C. armeniaca), tarsi paler with tarsomeres 2–4 of proleg dorsally yellow (protarsus dorsally dark brown to black in C. armeniaca), short ventral pile on metafemur black except for the yellow pile on basal 1/5 (in C. armeniaca metafemur with ventral pile yellow, except for the apical 1/4 with black pile), terga II–III partly pruinose (entirely shiny in C. armeniaca), abdomen more elongated, less oval compared to C. armeniaca, pile on sternum III medially predominantly adpressed (C. armeniaca has pile on sternum III medially predominantly erect) and surstylus with a less distinct kink halfway on the ventral margin. Although C. longifacies keys out to C. armeniacaintheidentificationkeyprovidedbyStåhls&Barkalov(2017),itismorphologicallycloser to C. caerulescens (Meigen, 1822), but it differs in several ways including more protruding and less pruinose face and tergum III with yellow pile only (tergum III partly black pilose in C. caerulescens). European Journal of Taxonomy 1023: 1–181 (2025) 82 Etymology The species name is derived from the Latin word ‘longus’ meaning ‘long’ (Brown 1956: 494) and the Latin word ‘facies’ meaning ‘face’ (Brown 1956: 313) and it refers to its distinctly protruding face. Species epithet to be treated as a noun in apposition. Material examined Holotype GEORGIA•♂;Mtskheta-Mtianeti,Lutkhubi;42.3984°N,44.7996°E;2068ma.s.l.;8May2023; S. Bot leg.; ZFMK, SB.003148 = ZFMK-TIS-8027991. Paratypes GEORGIA – Mtskheta-Mtianeti•1♂;Lutkhubi;42.3936°N,44.7923°E;1760ma.s.l.;8May2023; F. Van de Meutter leg.; FMT, ZFMK-TIS-8027953. Description Male Length. Body 8.5–11 mm, wing 7–8.5 mm. head. Face bare, with facial tubercle, black, protruding downwards, shiny except for a pruinose band below antennae and slightly pruinose oblique stripe at lateral parts of face. Mala shiny. Parafacia black, at widest point ca 0.8 times as wide as width of postpedicel, shiny except dorsal corners, with yellow pile. Lengthofeyecontiguityca0.8timesaslongasfrons.Angleofapproximationofeyesca95°.Frontal triangleblack,shiny,longyellowpilose,withmedialfrontalsulcus.Ocellartrianglewithcaanterior⅔ blackpilose,caposterior⅓yellowpilose.Dorsalmarginofocciputwithlongyellowpileandsome sparse black pile intermixed. Lunule black, medial arm on lunule absent, antennal fossa present. Scape black with predominantly yellow setae; pedicel basally black, apically dark orange, with predominantly yellow setae; postpedicel about as high as wide, rounded, entirely orange or basally orange, apically dark orange. Arista black, with short pile, pile 0.5 times as long as width of arista at base. Eye bare. t horax .Scutumblack,shiny,finelypunctured,withlongerectyellowpile,mediallyandinbetween wing bases intermixed with sparse black pile; lateral margin of scutum with some black setae, postalar callus with or without black setae. Scutellum black, shiny, entirely with yellow pile, posterior margin with yellow not so strong setae. Pleura black, slightly pruinose, with yellow pile, dorsal and ventral pile patches on katepisternum connected. Haltere with pedicellum yellow, capitulum dark or orange. Wing. Wing including alula entirely microtrichose; veins black, all cross-veins infuscated; stigma yellowbrown; vein R4+5 not distinctly curved. L egs . Coxae and trochanters black. Femora black except apical 1/10 yellow. Tibiae black except ca basal 1/3 and apical 1/5 yellow. Tarsi yellow except basitarsomere and fourth tarsomere dorsally brown and fifthtarsomereblack.Legsmainlyyellowpilose,metafemurventrallywithlongandshortpile;ofshort pile, basal 1/5 yellow, remainder of pile predominantly black. abdomen. Terga I–IV with erect yellow pile, pile laterally longer, terga I–IV shiny except medial half of terga I–II and tergum III anteromedially pruinose. Sternum I pruinose, sterna II–IV shiny, sterna I–II with erect yellow pile, sterna III–IV with yellow erect pile laterally, pile medially adpressed and yellow, except posteromedial on sternum IV where also with black adpressed pile. Genitalia with surstylus longer than wide, tapering. Dorsal lobes of postgonite pointed, ventral lobes rounded. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 83 Genetics DNA barcodes of C. longifacies sp. nov. were resolved into a cluster with high support (BS = 100%) together with the barcodes of C. armeniaca and C. caerulescens. All sequences of C. caerulescens cluster together, while C. longifacies barcodes are grouped with those of C. armeniaca. Remarks Genetically indistinguishable from C. armeniaca, despite the many consistent distinct morphological differences between the two species. Biology Inmountainsbetween1760–2068ma.s.l.Theholotypewascollectedwithahandnetwhenflying throughafloweringwillowalongamountainstreamjustbelowthesnowline,theparatypewasfeeding on male willow catkins a bit lower along the same mountain stream. Fig. 41. Cheilosia (Taeniochilosia) longifacies sp.nov.,holotype,♂(ZFMK,ZFMK-TIS-8027991). A. Habitus, lateral view; body length 8.5 mm. B. Head, lateral view; eye width 1.3 mm. C. Habitus, dorsal view; body length 8.5 mm. D. Surstylus, lateral view. E. Postgonite, lateral view. Scale bars: A–C not to scale; D–E in µm. European Journal of Taxonomy 1023: 1–181 (2025) 84 Distribution So far only known from the type locality in the Greater Caucasus. Cheilosia (Eucartosyrphus) longula (Zetterstedt, 1838) Fig. 42 Eristalis longula Zetterstedt, 1838: 613. Cheilosia longula – Barkalov 1993: 712. Fig. 42. Cheilosia (Eucartosyrphus) longula (Zetterstedt, 1838). A.♂(SBA,SB.004474);habitus,lateral view; collected in Finland; body length 6.9 mm. B.♂(SBA,SB.004475);habitus,dorsalview;collected in the Netherlands; body length 7.8 mm. C–D.♀(ASW,ZFMK-TIS-8009291);collectedinGeorgia; body length 7.4 mm. C. Habitus, lateral view. D. Habitus, dorsal view. E.♂(SBA,SB.004476);head, lateral view; collected in Norway; eye width 1.2 mm. F.♀(ZFMK-TIS-8009291;ASW);head,lateral view; collected in Georgia; eye width 1.0 mm. Not to scale. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 85 Differential diagnosis Cheilosia longula is a small (body length: 6–9 mm), slender species, characterized by a bare face, bare eye, bicoloured legs, hyaline wings and lunule with reduced medial arm. Similar to C. ruffipes and C. scutellata, but these species have a broad facial tubercle, semicircular in dorsal view, while in C. longula the facial tubercle is narrow, almost conical in dorsal view. Like C. flavissima, but that species is paler, in the male the face is partly yellow, and the wing base is yellow (black in C. longula) and in the female the proand mesofemur and scutellum are completely yellow (proand mesofemur black with narrow yellow apices and scutellum at least along anterior margin black in C. longula). Material examined GEORGIA – Mtskheta-Mtianeti•1♀;42.6669°N,44.6127°E;2139ma.s.l.;13Jul.2019;A.Ssymank leg.; ASW, ZFMK-TIS-8009291. Genetics DNA barcodes of C. longula from Europe, Russian Far East and the Caucasus cluster together with high support (BS = 99.9%). Remarks ReportedfromGeorgiaforthefirsttime. Distribution Europe, Caucasus, eastwards to eastern Siberia. Within the Caucasus, occurrence in countries other than Georgia uncertain. Barkalov (1993) reports it from the Greater Caucasus without specifying the country. Not reported from the Russian Caucasus in the Russian Checklist (Barkalov & Mutin 2018). Cheilosia (Taeniochilosia) lukashovae Barkalov, 1993 Fig. 43 Cheilosia lukashovae Barkalov, 1993: 702. Cheilosia lukashovae – Barkalov & Ståhls 1997: 40. — Barkalov & Mutin 2018: 486. Differential diagnosis Cheilosia lukashovae belongs to the subgenus Taeniochilosia by the combination of bare eye, black legs andtheanteriorprocessoflunulanotbroadlyconfluentwiththeface(Barkalov & Ståhls 1997). The male C. lukashovae is easily distinguishable amongst those of the other Taeniochilosia occurring in the Caucasus by the combination of the pruinose parafacia, scutum and sterna, and the long surstylus ca three times as long as wide (at most two times as long as wide in the other species). The female is the only Taeniochilosia in the Caucasus with the combination of a narrow face (at level of antennal base narrower than eye) and scutum with erect yellow pile, with longer black pile intermixed (vs scutum with adpressed pile in the other species). Material examined Collected in 2018, 2019, 2021 and 2023, but 2018 records were not published in Mengual et al. (2020). Hence, all records are reported here. GEORGIA – Imereti•8♂♂;Abastumani,roadAbastumanitoSairme;41.8245°N,42.8482°E; 2165 m a.s.l.; 10 Jun. 2019; J.H. Skevington leg.; CNC, CNC1386098, CNC1386110 to CNC1386113, CNC1386115,CNC1386116,CNC1386120•1♀;samedataasforpreceding;CNC,CNC1386117 European Journal of Taxonomy 1023: 1–181 (2025) 86 •1♂,1♀;roadAbastumanitoSairme;41.8242°N,42.8472°E;2150ma.s.l.;10Jun.2019;F.Van deMeutterleg.;FMT•1♂;roadfromAbastumanitoSairme;41.8385°N,42.8194°E;2260ma.s.l.; 10Jun.2020;X.Mengualleg.;ZFMK,ZFMK-DIP-00066342=ZFMK-TIS-8008755•1♀;road fromAbastumanitoSairme;41.8643°N,42.7784°E;1830ma.s.l.;10Jun.2020;X.Mengual leg.; ZFMK, ZFMK-DIP-00066347. – Kakheti•5♂♂;BatsaraNatureReserve;42.26493°N, 45.25918°E;1955ma.s.l.;29May2022;X.Mengualleg.;ZFMK,ZFMK-DIP-00094022=ZFMKTIS-8014590,ZFMK-DIP-00094023toZFMK-DIP-00094025,ZFMK-DIP-00094027•1♂;Batsara NatureReserve;42.28654°N,45.24221°E;2065ma.s.l.;29May2022;X.Mengualleg.;ZFMK, ZFMK-DIP-00094031=ZFMK-TIS-8014591•1♀;samedataasforpreceding;ZFMK,ZFMKDIP-00094032 = ZFMK-TIS-8014592. – Mtskheta-Mtianeti•1♀;Kobi;42.5052°N,44.4991°E; 2860ma.s.l.;14Jul.2019;A.Ssymankleg.;ASW,ZFMK-TIS-8009290•2♀♀;TbilisiN.P.;41.880°N, 45.023°E;1289ma.s.l.;4May2023;S.Botleg.;SBA,SB.002395,SB.002396•5♂♂,1♀♀;Tbilisi N.P.;41.877°N,45.0138°E;1250ma.s.l.;4May2023;F.VandeMeutterleg.;FMT•2♂♂;Tbilisi N.P.;41.8802°N,45.0220°E;1279ma.s.l.;4May2023;W.Opdekampleg.;WOR,A015,A053• 2♀♀;samedataasforpreceding;WOR,A037,A038•2♀♀;TbilisiN.P.;41.8787°N,45.0288°E; 1316 m a.s.l.; 9 May 2023; S. Bot leg.; SBA, SB.002393, SB.002394. – Racha-Lechkhumi and Kvemo Svaneti•1♂;42.8880°N,43.2330°E;1900ma.s.l.;30Jun.2018;S.Botleg.;SBA,SB.002383.– Samegrelo-Zemo Svaneti•3♂♂;42.9480°N,43.0200°E;2800ma.s.l.;25Jun.2018;S.Botleg.; SBA,SB.002379•3♀♀;samedataasforpreceding;SBA,SB.002380,SB.002381•7♂♂,5♀♀; 14kmEofMestia;43.0256°N,42.8908°E;2550ma.s.l.;13Jun.2019;F.VandeMeutterleg.; FMT•1♂,1♀;43.0259°N,42.9103°E;2863ma.s.l.;13Jun.2019;J.H.Skevingtonleg.;CNC, CNC1386386,CNC1386387•1♂;43.0254°N,42.8906°E;2550ma.s.l.;13Jun.2019;X.Mengual leg.;ZFMK,ZFMK-DIP-00066341•7♀♀;samedataasforpreceding;ZFMK,ZFMK-DIP-00066344, ZFMK-DIP-00066345 = ZFMK-TIS-8008757, ZFMK-DIP-00066346, ZFMK-DIP-00066348 to ZFMKDIP-00066351•7♂♂;Mestia;43.02°N,42.87°E;2350ma.s.l.;13Jun.2019;J.vanSteenisleg.; JSB,2019-00.912to2019-00.918•5♀♀;samedataasforpreceding;JSB,2019-00.919to201900.923•1♂;43.0260°N,42.8900°E;2566ma.s.l.;13Jun.2019;S.Botleg.;SBA,SB.002385 •1♀;samedataasforpreceding;SBA,SB.002386•1♂;43.0280°N,42.9100°E;2834ma.s.l.; 13Jun.2019;S.Botleg.;SBA,SB.002387•3♂♂;42.9471°N,43.0671°E;2257ma.s.l.;15Jun. 2019;J.H.Skevingtonleg.;CNC,CNC1386539,CNC1386555,CNC1386556•5♀♀;samedataasfor preceding;CNC,CNC1386520,CNC1386530,CNC1386536,CNC1386540,CNC1386553•2♀♀; Ushguli;42.94°N,43.05°E;2220ma.s.l.;15–17Jun.2019;J.vanSteenisleg.;Malaisetrap;JSB,201900.924,2019-00.925•3♂♂,1♀;hilltop7kmWofUshguli;42.9370°N,42.9061°E;2615ma.s.l.; 16Jun.2019;F.VandeMeutterleg.;FMT•2♂♂;42.9062°N,42.9370°E;2615ma.s.l.;16Jun.2020; X.Mengualleg.;ZFMK,ZFMK-DIP-00066339,ZFMK-DIP-00066340=ZFMK-TIS-8008753•1♀; Ushguli;42.94°N,43.07°E;2300ma.s.l.;16Jun.2019;J.vanSteenisleg.;JSB,2019-00.926•1♀; SofDavberi;42.90°N,42.93°E;2600ma.s.l.;17Jun.2019;J.vanSteenisleg.;JSB,2019-00.927 •1♂;42.8980°N,43.0080°E;2601ma.s.l.;18Jun.2019;S.Botleg.;SBA,SB.002382•2♀♀; passfromUshgulitoTsana;42.9142°E,43.0911°N;2575ma.s.l.;20Jun.2019;F.VandeMeutter leg.;FMT•1♂;43.0275°N,42.9115°E;2887ma.s.l.;14Jul.2021;S.Botleg.;SBA,SB.002384.– Samtskhe-Javakheti•5♀♀;BorjomiN.P.;41.7280°N,43.3640°E;2327ma.s.l.;9Jun.2019;S.Bot leg.;SBA,SB.002388toSB.002392•1♂;roadfromSakiretoTsikhisjvari;41.7251°N,43.3605°E; 2519ma.s.l.;9Jun.2020;X.Mengualleg.;ZFMK,ZFMK-DIP-00066343•2♀♀;samedataas forpreceding;ZFMK,ZFMK-DIP-00066352,ZFMK-DIP-00066353•1♂;Borjomi;41.7299°N, 43.3684°E;2245ma.s.l.;9Jun.2019;J.H.Skevingtonleg.;CNC,CNC1385983•5♂♂;Borjomi; 41.72°N,43.36°E;2250ma.s.l.;9Jun.2019;J.vanSteenisleg.;JSB,2019-00.898to2019-00.902• 5♀♀;samedataasforpreceding;JSB,2019-00.903to2019-00.907•6♂♂,4♀♀;roadfromSakire toTsikhisjvari;41.7251°N,43.3605°E;2519ma.s.l.;9Jun.2019;F.VandeMeutterleg.;FMT• 2♂♂;Abastumani;41.83°N,42.81°E;2260ma.s.l.;10Jun.2019;J.vanSteenisleg.;JSB,201900.908,2019-00.909•1♀;samedataasforpreceding;JSB,2019-00.910•1♂;Abastumani;41.82°N, 42.84°E;2100ma.s.l.;11Jun.2019;J.vanSteenisleg.;JSB,2019-00.911•10♂,7♀♀;Kodiani; BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 87 41.7305°N,43.3537°E;2160ma.s.l.;10May2023;F.VandeMeutterleg.;FMT•3♂♂;Sakire; 41.7301°N,43.3306°E;1820ma.s.l.;10May2023;F.VandeMeutterleg.;FMT•7♂♂;Kodiani; 41.7300°N,43.3485°E;2080ma.s.l.;10May2023;W.Opdekampleg.;WOR,A014,A020,A026, A028,A040,A045,A047•4♀♀;samedataasforpreceding;WOR,A001,A017,A034,A041•2♂♂; Kodiani;41.7268°N,43.3490°E;2150ma.s.l.;10May2023;W.Opdekampleg.;WOR,B007,B014 •1♀;samedataasforpreceding;WOR,B012. RUSSIA – North Ossetia-Alania•2♂♂;WofDigoria,ChefandzarmireinUrukhRivervalley; 43.5149°N,42.9186°E;2289ma.s.l.;2–3Jun.2018;A.Przhiboroleg.;yellowplates;ZFMK,ZFMKFig. 43. Cheilosia (Taeniochilosia) lukashovae Barkalov, 1993. Collected in Georgia. A.♂(SBA, SB.002385); habitus, lateral view; body length 6.7 mm. B.♂(SBA,SB.002384);head,lateralview; eye width 0.9 mm. C.♂(SBA,SB.002383);habitus,dorsalview;bodylength6.5mm.D.♀(SBA, SB.002396); head, lateral view; eye width 1.1 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 88 DIP-00078666=ZFMK-TIS-8009573,ZFMK-DIP-00078670=ZFMK-TIS-8009577•7♀♀;same data as for preceding; ZFMK, ZFMK-DIP-00078661 = ZFMK-TIS-8009568, ZFMK-DIP-00078662 = ZFMK-TIS-8009569, ZFMK-DIP-00078664 = ZFMK-TIS-8009571, ZFMK-DIP-00078665 = ZFMKTIS-8009572, ZFMK-DIP-00078667 = ZFMK-TIS-8009574, ZFMK-DIP-00078668 = ZFMKTIS-8009575, ZFMK-DIP-00078669 = ZFMK-TIS-8009576. Genetics All DNA barcodes of C. lukashovae are resolved in a group with high support (BS = 100%). Remarks ReportedfromGeorgiaforthefirsttime. Biology During our expeditions, collected between 4 May and 20 June at altitudes between 1250 and 2860 m a.s.l. Males have been found hovering and sitting on the ground near hilltops and at the upper margin of slopingmeadowsnearforest.BothsexesvisitflowersofCaltha palustris and Ranunculus sp. Distribution Northern Caucasus (Russia) and Georgia. Cheilosia (Cheilosia) megaclama sp. nov. urn:lsid:zoobank.org:act:1F1630DC-842F-4C5E-81C8-754C8C524F99 Figs 44–45 Differential diagnosis Cheilosia megaclama sp. nov. belongs to the subgenus Cheilosia. In the Caucasus, the male can be confused with those of C. aurantia sp. nov. and C. albipila. It is best distinguished from that of C. aurantia by the yellow pile on the eye (Fig. 44B) (longer and black in C. aurantia Fig. 9A) and it can be separated from that of C. albipila by the wider face, below the antenna about as wide as an eye (Fig. 44D) (about half as wide as an eye in C. albipila) and the katepisternal hair patches that are separated or only narrowly connected by short pile (katepisternal hair patches connected broadly by long pile in C. albipila). Because the eyes are bare in the female, contrary to the male, the female of C. megaclama can be confused with those of C. uviformis and C. atypica, but it differs from the former by the truly bare eye (some short scattered pile on eye in C. uviformis) and wider parafacia (Fig. 45D), and it can be distinguished from the latter by the darker legs: tibiae with black ring and tarsi mainly black(tibiaewithindistinctringandtarsidorsallymostlyyellow,exceptfirst,fourthandfifthsegments ofprotarsusandfifthsegmentofmesotarsusblackinC. atypica). Cheilosia megaclama is especially similar to the extralimital C. clama Claussen & Vujić, 1995 occurring in Central Europe. The male of C. megaclama differs from that of C. clama by a larger body size (average 10.5 mm instead of maximum 8.8 mm in C. clama), slightly narrower face, shiny parafacia (parafacia pruinose in C. clama), longer eye contiguity (0.8 times the length of frons in C. megaclama vs 0.5 to 0.55 in C. clama), angle of approximationofeyessmaller(90°vs100–110°inC. clama), wing veins blackish in basal half in C. megaclama instead of yellow in C. clama, metafemur ventrally with predominantly orange instead of black setae in C. clama, and differences in the male genitalia: postgonite with ventral lobe shorter and dorsal lobe longer. The female of C. megaclama differs from that of C. clama by larger size (on average over 9 mm vs around 7 mm), the longer body pile (pile much longer on, e.g., scutum, pleura and abdomen in C. megaclama) and by wing veins blackish in basal half in C. megaclama instead of yellow in C. clama. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 89 Etymology ThespeciesnamederivesfromtheGreekprefix‘mega-’ meaning ‘large’ (Brown 1956: 517) applied to the name clama to mean ‘large clama’ and it refers to the general similar appearance of our new species to C. clama and the difference in size. Species epithet to be treated as a noun in apposition. Material examined Holotype GEORGIA•♂;Mtskheta-Mtianeti,Lutkhubi;42.3984°N,44.7996°E;2068ma.s.l.;8May2023; S. Bot leg.; ZFMK, SB.003216 = ZFMK-TIS-8027979. Paratypes GEORGIA – Mtskheta-Mtianeti•1♂;Lutkhubi;42.3984°N,44.7996°E;2068ma.s.l.;8May2023; S.Botleg.;SBA,SB.003217•1♀;samedataasforpreceding;SBA,SB.003218=ZFMK-TIS-8027980 •1♂;Lutkhubi;42.3936°N,44.7923°E;1760ma.s.l.;8May2023;F.VandeMeutterleg.;FMT• 1♀;samedataasforpreceding;ZFMK•1♂;Lutkhubi;42.3989°N,44.7995°E;2100ma.s.l.;8May 2023; W. Opdekamp leg.; ZFMK, D004. – Samegrelo-Zemo Svaneti•1♀;Ushguli,closetoriver Inguri;42.9500°N,43.0719°E;2270ma.s.l.;15Jun.2019;F.VandeMeutterleg.;FMT,ZFMKTIS-8012674. – Samtskhe-Javakheti•1♂;Kodiani;41.7268°N,43.3490°E;2150ma.s.l.;10May 2023; W. Opdekamp leg.; WOR, B002. Description Male Length. Body 10.5–11 mm, wing 8–8.5 mm. head. Face black, bare, with facial tubercle, thick pruinose below lunule, slightly pruinose, except facial tubercle and mouth edge shiny and with dense pruinose band below lunule, below lunule slightly less wide than an eye. Parafacia black, shiny or slightly pruinose, white pilose, about 0.8 times as wide as postpedicel. Clypeus shiny, about 1.5 to 1.9 times as long as wide measured from the midline. Frontal triangle black, pruinose, swollen, with long black and yellow pile, black pile usually dominating, with medial frontal sulcus. Length of eye contiguity about 0.8 times the length of frons. Angle of approximationofeyes90°.Verticaltriangleblack,ocellartrianglelongblackandyellowpilose.Occiput pruinose, short yellow and long black pilose. Lunule dark orange to blackish, with distinct medial arm, separating acetabula. Scape black; pedicel black or dark orange; postpedicel orange, sometimes dorsal outer corner darkened, 1.25 to 1.5 times as wide as high; arista black, thickened in basal one third, with very short pile, pile much shorter than diameter of arista at base. Eye entirely covered with yellow pile. thorax.Scutumblack,shiny,finelypunctured,witherectyellow-whitepile,withafewblackpile intermixed near wing base, on postalar callus and in anterolateral corners. Scutellum shiny or slightly pruinose, with long erect yellow-white pile, without setae along posterior margin. Pleura black, slightly pruinose, with yellow pile; metasternum with long whitish pile; dorsal and ventral pile patches on katepisternum narrowly separated but usually connected by shorter pile. Haltere pedicellum orange, capitulum dark brown. Wing. Wing including alula entirely microtrichose, hyaline except in anterior half where slightly dark brown infuscated, wing veins brown in the basal part and black in the apical part of the wing. Legs. With black and yellow piles. Coxae, trochanters black. Femora black except apices narrowly yellow, with black and yellow piles; metafemur ventrally with orange semi-adpressed setae, with a few black ones intermixed. Tibiae orange except with black ring below the middle occupying one third of proand mesotibia and 40% of metatibia. Protarsus black except basal three tarsomeres ventrally orange; European Journal of Taxonomy 1023: 1–181 (2025) 96 Genetics DNA sequences for European and Caucasian specimens of C. nebulosa cluster together with high support (BS = 100%). Remarks ReportedfromtheCaucasusforthefirsttime. Biology During our expeditions, collected between 6 May and 9 May at an altitude between 1316 and 2180 m a.s.l. Locally abundant with several hundreds seen on alpine meadows, feeding on Salix sp. and males hovering at hilltops. Distribution Europe, Caucasus, eastward to West and Central Siberia. Fig. 48. Cheilosia (Cheilosia) nebulosa Verrall, 1871. Collected in Georgia. A.♂(SBA,SB.002501); habitus, lateral view; body length 8.2 mm. B.♂(SBA,SB.002501);head,lateralview;eyewidth 1.1 mm. C.♂(SBA,SB.002514);habitus,dorsalview;bodylength9.3mm.D.♀(SBA);head,lateral view; eye width 0.9 mm. Not to scale. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 97 Cheilosia (Taeniochilosia) nigripes (Meigen, 1822) Fig. 49 Syrphus nigripes Meigen, 1822: 282. Cheilosia nigripes – Stackelberg & Richter 1968: 247. — Stackelberg 1970: 58. — Tóth 1986: 94. — Peck1988:110.—Barkalov1993:708.—Barkalov&Ståhls1997:70,fig.41.—Gujabidze2002: 245. — Mengual et al. 2020: 26. Differential diagnosis Cheilosia nigripes belongs to the subgenus Taeniochilosia by the combination of bare eye, black legsandtheanteriorprocessoflunulanotbroadlyconfluentwiththeface(Barkalov&Ståhls1997). Within TaeniochilosiaoccurringintheCaucasusitcanbeeasilyidentifiedbytheshinysternaII– IV (pruinose in all other Taeniochilosia in the Caucasus). Cheilosia nigripes from the Caucasus is morphologically slightly different from specimens studied from Europe and the Russian Far East: the male is more extensively pruinose, with the frons, posterior anepisternum and katepisternum pruinose and the pruinosity on anterior part of scutum reaches lateral margin; the scutum is slightly less coarsely punctured; pile on lateral margin of tergum IV longer, more erect and usually yellow; and pile on lateral part of sternum III longer. Females from the Caucasus are also more pruinose on the posterior anepisternum and katepisternum, and the pruinosity on anterior part of scutum reaches the lateral margins of the scutum. Due to the more extensive pruinosity, the Caucasian individuals are very similar to extralimital C. vicina (Zetterstedt, 1849), although the pruinosity in C. nigripes from the Caucasus is less dense and the clypeus shorter (in the mid-line, at the most 1.25 times as long as its maximum width vs 1.75–2timesaslongasitsmaximumwidth).ThemalegenitaliaarefiguredinBarkalov&Ståhls(1997). Material examined Collected in 2018, 2019, 2021, 2022 and 2023, but 2018 records were not published in Mengual et al. (2020). Thus, all our records are reported here. ARMENIA – Ararat Province•1♂;surroundingsGeghardMonastery;40.13859°N,44.81728°E; 1720 m a.s.l.; 22 May 2022; X. Mengual leg.; ZFMK, ZFMK-DIP-00093547. – Gegharkunik Province •18♂♂;SevanN.P.;40.56383°N,45.01303°E;1963ma.s.l.;23May2022;X.Mengualleg.;ZFMK, ZFMK-DIP-00093607 = ZFMK-TIS-8014580, ZFMK-DIP-00093608 to ZFMK-DIP-00093612, ZFMK-DIP-00093614 to ZFMK-DIP-00093618, ZFMK-DIP-00093620 to ZFMK-DIP-00093624, ZFMK-DIP-00094163,ZFMK-DIP-00094165•10♀♀;samedataasforpreceding;ZFMK,ZFMKDIP-00093625 to ZFMK-DIP-00093631, ZFMK-DIP-00093633, ZFMK-DIP-00093634, ZFMKDIP-00094166•1♂;samedataasforpreceding;A.andG.Lehmannleg.;ZFMK,ZFMK-DIP-00094162. – Kotayk Province•20♂♂;Tsaghkadzor,Y.S.U.RestHouse;40.53362°N,44.70302°E;1915ma.s.l.; 23 May 2022; X. Mengual leg.; ZFMK, ZFMK-DIP-00093650 = ZFMK-TIS-8014581, ZFMKDIP-00093644 to ZFMK-DIP-00093649, ZFMK-DIP-00093652 to ZFMK-DIP-00093656, ZFMKDIP-00093659, ZFMK-DIP-00093660, ZFMK-DIP-00094509, ZFMK-DIP-00093661, ZFMKDIP-00093662,ZFMK-DIP-00093678,ZFMK-DIP-00093679,ZFMK-DIP-00093680•7♀♀;same data as for preceding; ZFMK, ZFMK-DIP-00093665, ZFMK-DIP-00093668 to ZFMK-DIP-00093671, ZFMK-DIP-00093675,ZFMK-DIP-00093677•1♂;Tsaghkadzor,Y.S.U.RestHouse;40.53362°N, 44.70302°E;1915ma.s.l.;23May2022;T.Saldenleg.;yellowpantrap;ZFMK,ZFMK-DIP-00094334 •5♂♂;Tsaghkadzorarea,towardsGrandPalaceHotel;40.53310°N,44.69966°E;1975ma.s.l.;24May 2022; X. Mengual leg.; ZFMK, ZFMK-DIP-00093684, ZFMK-DIP-00093689, ZFMK-DIP-00093693 toZFMK-DIP-00093695•4♀♀;samedataasforpreceding;ZFMK,ZFMK-DIP-00093696,ZFMKDIP-00093697, ZFMK-DIP-00093699, ZFMK-DIP-00093700. – Syunik Province•2♂♂;fromLichk totheZvaravankMonastery;39.05497°N,46.17135°E;1765ma.s.l.;16May2022;X.Mengual European Journal of Taxonomy 1023: 1–181 (2025) 98 leg.;ZFMK,ZFMK-DIP-00093044=ZFMK-TIS-8014428,ZFMK-DIP-00093046•3♀♀;samedata as for preceding; ZFMK, ZFMK-DIP-00093042 = ZFMK-TIS-8014430, ZFMK-DIP-00093038 = ZFMK-TIS-8014435,ZFMK-DIP-00093039•23♂♂;20kmNofMeghri;39.07882°N,46.17894°E; 1865 m a.s.l.; 17 May 2022; X. Mengual leg.; ZFMK, ZFMK-DIP-00093105 to ZFMK-DIP-00093127 •6♀♀;samedataasforpreceding;ZFMK,ZFMK-DIP-00093099toZFMK-DIP-00093103,ZFMKDIP-00093129•1♀;nearGorayk,SpandarianReservoir;39.68451°N,45.77747°E;2078ma.s.l.; 19May2022;X.Mengualleg.;ZFMK,ZFMK-DIP-00093346•4♂♂;Spandaryan,smallriver; 39.621045° N, 45.910242° E; 1986 m a.s.l.; 19 May 2022; X. Mengual leg.; ZFMK, ZFMKDIP-00093160,ZFMK-DIP-00093162,ZFMK-DIP-00093193,ZFMK-DIP-00093236•2♀♀;samedata as for preceding; ZFMK, ZFMK-DIP-00093166, ZFMK-DIP-00093253. – Vayots Dzor Province•1♀; WofSaravan;39.71843°N,45.63076°E;1590ma.s.l.;19May2022;X.Mengualleg.;ZFMK,ZFMKDIP-00093442. – Yerevan Province•1♂;YerevanBotanicalGarden;40.21197°N,44.55889°E; 1237 m a.s.l.; 14–21 May 2022; B. Rulik, B. Müller leg.; Malaise trap; ZFMK, ZFMK-DIP-00094194 •3♀♀;samedataasforpreceding;ZFMK,ZFMK-DIP-00094192,ZFMK-DIP-00094195,ZFMKDIP-00094196•6♂♂;YerevanBotanicalGarden;40.213077°N,44.55978°E;1244ma.s.l.;21May 2022; X. Mengual leg.; ZFMK, ZFMK-DIP-00093504 to ZFMK-DIP-00093508, ZFMK-DIP-00094493 •3♀♀;samedataasforpreceding;ZFMK,ZFMK-DIP-00093509toZFMK-DIP-00093511. GEORGIA – Kakheti•1♀;LagodekhiN.P.;41.877°N,46.384°E;2652ma.s.l.;3Jul.2021;S.Bot leg.;SBA,SB.002471•1♂;LagodekhiN.P.;41.9223°N,46.3726°E;2758ma.s.l.;4Jul.2021; S.Botleg.;SBA,SB.002466•1♂;BatsaraNatureReserve;42.22238°N,45.30352°E;806ma.s.l.; 28May2022;X.Mengualleg.;ZFMK,ZFMK-DIP-00093956•1♀;samedataasforpreceding;ZFMK, ZFMK-DIP-00093971•3♂♂;nearTetriTsklebi;41.86354°N,45.31890°E;1317ma.s.l.;1Jun. 2022; X. Mengual leg.; ZFMK, ZFMK-DIP-00094095, ZFMK-DIP-00094097, ZFMK-DIP-00094101 •1♀;samedataasforpreceding;ZFMK,ZFMK-DIP-00094104•7♂♂;DedoplisTskaro;41.4848°N, 46.0947°E;750ma.s.l.;30April2023;S.Botleg.;SBA,SB.002449toSB.002455•6♀♀;same dataasforpreceding;SBA,SB.002479toSB.002484•7♂♂,6♀♀;DedoplisTskaro;41.4856°N, 46.0947°E;750ma.s.l.;30April2023;F.VandeMeutterleg.;FMT•3♂♂;DedoplisTskaro; 41.4852°N,46.0950°E;750ma.s.l.;30April2023;W.Opdekampleg.;WOR,C001,C010,C017 •3♀♀;samedataasforpreceding;WOR,C008,C009,C023•2♂♂;DedoplisTskaro;41.4845°N, 46.0928°E;800ma.s.l.;30April2023;W.Opdekampleg.;WIR,B012,B014•4♀♀;samedata as for preceding; WOR, B004, B005, B008, B015. – Mtskheta-Mtianeti•1♂;Juta;42.5838°N, 44.7486°E;2190ma.s.l.;10Jul.2019;A.Ssymankleg.;ASW,ZFMK-TIS-8009286•3♂♂; TbilisiN.P.;41.8808°N,45.0203°E;1270ma.s.l.;27May2022;X.Mengualleg.;ZFMK,ZFMKDIP-00093887,ZFMK-DIP-00093890,ZFMK-DIP-00093891•3♀♀;samedataasforpreceding; ZFMK,ZFMK-DIP-00093897,ZFMK-DIP-00093898,ZFMK-DIP-00093900•9♂♂;TbilisiN.P.; 41.8811°N,45.02080°E;1275ma.s.l.;27May–1Jun.2022;X.Mengualleg.;Malaisetrap;ZFMK, ZFMK-DIP-00094274, ZFMK-DIP-00094317, ZFMK-DIP-00094370, ZFMK-DIP-00094372, ZFMKDIP-00094373,ZFMK-DIP-00094375,ZFMK-DIP-00094467toZFMK-DIP-00094469•7♀♀;same data as for preceding; ZFMK, ZFMK-DIP-00094267, ZFMK-DIP-00094268, ZFMK-DIP-00094309, ZFMK-DIP-00094382,ZFMK-DIP-00094449,ZFMK-DIP-00094450,ZFMK-DIP-00094457•1♀; TbilisiN.P.;41.8808°N,45.0203°E;1270ma.s.l.;1Jun.2022;X.Mengualleg.;ZFMK,ZFMKDIP-00094161•10♂♂;TbilisiN.P.;41.880°N,45.023°E;1289ma.s.l.;4May2023;S.Botleg.;SBA, SB.002456toSB.002465;SBA•4♀♀;samedataasforpreceding;SBA,SB.002475toSB.002478• 23♂♂,6♀♀;TbilisiN.P.;41.877°N,45.0138°E;1250ma.s.l.;4May2023;F.VandeMeutterleg.; FMT•6♂♂;TbilisiN.P.;41.8802°N,45.0220°E;1279ma.s.l.;4May2023;W.Opdekampleg.;WOR, A013,A016,A026,A041,A048,A049•3♀♀;samedataasforpreceding;WOR,A019,A024,A042• 5♂♂,Lutkhubi;42.3797°N,44.7969°E;1463ma.s.l.;6May2023;S.Botleg.;SBA,SB.002443to SB.002447•1♀;samedataasforpreceding;SBA,SB.002474•1♂;Lutkhubi;42.3938°N,44.7857°E; 2120ma.s.l.;6May2023;W.Opdekampleg.;WOR,E002•2♂♂,2♀♀;Lutkhubi;42.3936°N, BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 99 44.7923°E;1760ma.s.l.;8May2023;F.VandeMeutterleg.;FMT•1♂;Lutkhubi;42.4147°N, 44.7549°E;1240ma.s.l.;8May2023;F.VandeMeutterleg.;FMT•1♂;Tsinamkhari;42.3914°N, 44.7562°E;1200ma.s.l.;8May2023;W.Opdekampleg.;WOR,B011•1♀;Lutkhubi;42.3930°N, 44.7929°E;1734ma.s.l.;8May2023;W.Opdekampleg.;WOR,C013•1♂;Lutkhubi;42.3930°N, 44.7929°E;1734ma.s.l.;8May2023;W.Opdekampleg.;WOR,C023•1♂;TbilisiN.P.;41.8787°N, 45.0288°E;1316ma.s.l.;9May2023;S.Botleg.;SBA,SB.002448•1♂,1♀;Tbilisi,Mamkoda; 41.8339°N,44.8763°E;920ma.s.l.;9May2023;F.VandeMeutterleg.;FMT.–Racha-Lechkhumi and Kvemo Svaneti–•1♀;nearShovi;42.713°N,43.701°E;2022ma.s.l.;7Jul.2021;S.Botleg.; SBA,SB.002470•2♀♀;aboveGlola;42.668°N,43.630°E;2598ma.s.l.;9Jul.2021;S.Botleg.; SBA, SB.002468, SB.002469. – Samegrelo-Zemo Svaneti•1♀;Samegrelo-ZemoSvaneti,Mestia; 43.080°N,42.762°E;1800ma.s.l.;22Jun.2018;S.Botleg.;SBA,SB.002472=ZFMK-TIS-8009288 •1♀;42.9989°N,42.6501°E;1273ma.s.l.;13–14Jun.2019;X.Mengualleg.;Malaisetrap;ZFMK, ZFMK-DIP-00078732=ZFMK-TIS-8010120•1♀;43.1112°N,42.7434°E;1683ma.s.l.;14Jun. 2019;F.VandeMeutterleg.;FMT•1♂;samedataasforpreceding;FMT,ZFMK-TIS-8009615.– Samtskhe-Javakheti•1♀;BorjomiN.P.;41.857°N,43.208°E;1900ma.s.l.;18Jun.2018;S.Botleg.; SBA,SB.002473=ZFMK-TIS-80092871♂;Sakire-Tsikhisjvari;41.72°N,43.36°E;2250ma.s.l.; Fig. 49. Cheilosia (Taeniochilosia) nigripes (Meigen, 1822). Collected in Georgia. A.♂(SBA, SB.002449); habitus, lateral view; body length 8.8 mm. B.♂(SBA,SB.002465);head,lateralview; eye width 1.0 mm. C.♂(SBA,SB.002449);habitus,dorsalview;bodylength8.8mm.D.♀(SBA, SB.002477); head, lateral view; eye width 1.1 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 100 9Jun.2019;J.vanSteenisleg;JSB•1♂;41.7304°N,43.3342°E;1900ma.s.l.;9Jun.2019;F.Van deMeutterleg.;FMT,ZFMK-TIS-8009616•1♀;41.7251°N,43.3605°E;2519ma.s.l.;9Jun.2019; X.Mengualleg.;ZFMK,ZFMK-DIP-00066338=ZFMK-TIS-8008754•1♂;Saimre;41.86°N, 42.77°E;1830ma.s.l.;10Jun.2019;J.vanSteenisleg.;JSB,2019-00.956=ZFMK-TIS-8009605 •3♀♀;41.7772°N,42.8372°E;1368ma.s.l.;10–11Jun.2019;X.Mengualleg.;Malaisetrap; ZFMK, ZFMK-DIP-00078648 = ZFMK-TIS-8009655, ZFMK-DIP-00069422 = ZFMK-TIS-8009528, ZFMK-DIP-00069440=ZFMK-TIS-8009520•1♀;Abastumani,Otskheriver;41.77°N,42.83°E; 1360ma.s.l.;10–11Jun.2019;J.vanSteenisleg;Malaisetrap;JSB,2019-01.097•1♂;BorjomiN.P.; 41.864°N,42.789°E;1798ma.s.l.;11Jun.2019;S.Botleg.;SBA,SB.002467=ZFMK-TIS-8009289 •1♂;Sakire;41.7301°N,43.3306°E;1820ma.s.l.;10May2023;F.VandeMeutterleg.;FMT•3♂♂, 1♀;Borjomi;41.8098°N,43.3327°E;840ma.s.l.;12May2023;F.VandeMeutterleg.;FMT•1♂; Borjomi;41.8098°N,43.3327°E;850ma.s.l.;12May2023;W.Opdekampleg.;WOR,A026. Genetics In our NJ tree we have a cluster with high support (BS = 99.9%) comprising the barcodes of C. vicina, C. sahlbergi Becker, 1894, C. impudens Becker, 1894, and C. nigripes. Within this cluster, all sequences of C. nigripes from Europe and Caucasus are grouped together with one barcode of C. impudens. Biology During our expeditions, collected between 30 April and 9 July at an altitude between 750 and 2758 m a.s.l. C. nigripes was seen feeding on low herbaceous plants as Ranunculus sp. Distribution Palaearctic. Within the Caucasus known from Azerbaijan, Armenia, Georgia and Russia. Cheilosia (Cheilosia) orthotrichaVujić&Claussen,1994 Fig. 50 Cheilosia orthotrichaVujić&Claussen,1994:261. Differential diagnosis Cheilosia orthotricha is quite a large species (12–15 mm) characterized by the combination of a bare face, pilose eye, bicoloured legs and posterior margin of scutellum without bristles. It can be distinguished from most other Cheilosia with the same set of characters by the bare or sparsely pilose ventral part of the eye (entirely pilose in similar species). It forms a similar-looking trio with C. canicularis and C. himantopus, but generally in C. orthotricha pile on the pleura straight, unlike pile in C. canicularis and C. himantopus, which is wavy at apex, the pile on posterior anepisternum have straight apex (with wavy apex in the other two species) and face predominantly shiny (slightly pruinose in the other two species).ThemalegenitaliaarefiguredinVujić&Claussen(1994). Material examined Cheilosia orthotricha was not collected in 2018, but collected in 2023. GEORGIA – Mtskheta-Mtianeti•2♂♂;TbilisiN.P.;41.880°N,45.023°E;1289ma.s.l.;4May2023; S.Botleg.;SBA,SB.002715=ZFMK-TIS-8028449,SB.002714=ZFMK-TIS-8028450•2♀♀;same dataasforpreceding;SBA,SB.002712=ZFMK-TIS-8028009,SB.002713=ZFMK-TIS-8028010• 4♂♂,6♀♀;TbilisiN.P.;41.877°N,45.0138°E;1250ma.s.l.;4May2023;F.VandeMeutterleg.; FMT•1♂,1♀;samedataasforpreceding;ZFMK•1♂;TbilisiNationalPark;41.8802°N,45.0220°E; 1279ma.s.l.;4May2023;W.Opdekampleg.;WOR,A051•6♀♀;samedataasforpreceding;WOR, BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 101 A009,A011,A025,A043,A054,A055•1♀;Lutkhubi;42.3930°N,44.7929°E;1700ma.s.l.;6May 2023;W.Opdekampleg.;WOR,A022•2♀♀;Lutkhubi;42.3936°N,44.7923°E;1760ma.s.l.;8May 2023;F.VandeMeutterleg.;FMT•1♂;Lutkhubi;42.3930°N,44.7929°E;1700ma.s.l.;8May2023; W.Opdekampleg.;WOR,C032•1♂;TbilisiN.P.;41.8770°N,45.0137°E;1248ma.s.l.;9May2023; S.Botleg.;SBA,SB.002710•1♀;samedataasforpreceding;SBA,SB.002711. Genetics All DNA barcodes of C. orthotricha are clustered together with high support (BS = 99%). Within this cluster,twobarcodesfromGermanygrouptogether(BS=100%)andfivebarcodesfromGeorgiacluster together (BS = 100%). Fig. 50. Cheilosia (Cheilosia) orthotrichaVujić&Claussen,1994.CollectedinGeorgia.A.♂(SBA, SB.002710); habitus, lateral view; body length 13.5 mm. B.♂(SBA,SB.002710);head,lateralview; eye width 1.6 mm. C.♂(SBA,ZFMK-TIS-8028450);habitus,dorsalview;bodylength14.1mm. D.♀(SBA,SB.002711);head,lateralview;eyewidth1.5mm.Nottoscale. European Journal of Taxonomy 1023: 1–181 (2025) 102 Remarks ReportedfromtheCaucasus,andGeorgia,forthefirsttime.GeorgianindividualsofC. orthotricha are genetically different from European populations (2.43–2.55%). We also found small morphological differences between populations in both regions. Our sample size for populations in both areas is too small to understand this variation, and for now we consider all populations belonging to one species. Biology During our expeditions, collected between 4 May and 9 May at an altitude between 1248 and 1760 m a.s.l. Nearly always found in close vicinity of its food plant Petasites hybridus L. Both sexes sit on leaves of the plant. Distribution Europe, Caucasus (Georgia). Cheilosia (Taeniochilosia) ouwehandae Bot sp. nov. urn:lsid:zoobank.org:act:71A92808-13A0-4110-999C-5638704D54BF Fig. 51 Differential diagnosis Cheilosia ouwehandae sp. nov. is only known from the male holotype, thus the differential diagnosis applies to males only. Cheilosia ouwehandae belongs to the subgenus Taeniochilosia by the combination ofbareeye,blacklegsandtheanteriorprocessoflunulanotbroadlyconfluentwiththeface(Barkalov& Ståhls 1997). Genetically similar to C. aenigmatosa, it differs morphologically as follows: smaller (body size 6.5 mm vs 8–9.5 mm), face and parafacia slightly pruinose (more densely pruinose in C. aenigmatosa), facial tubercle better developed, projecting well beyond mouth edge (Fig. 51B) (less developed, less protruding, not beyond mouth edge in C. aenigmatosa; Fig. 2C), postpedicel basoventrally orange (black in C. aenigmatosa), frontal triangle with black pile (with large proportion of pile yellow in C. aenigmatosa), pile on scutum whitish instead of golden, posterior margin of scutellum with black setae instead of black pile and abdomen with more dense pruinosity. Cheilosia ouwehandae can be confused with extralimital C. sahlbergi and C. vangaveri Timon-David, 1937. It differs from C. sahlbergi and C. vangaveri by dense pruinose frons (slightly pruinose or shiny in C. sahlbergi, shiny in C. vangaveri), pruinose parafacia (shiny in C. sahlbergi and C. vangaveri), abdomen with completely yellow pile (partly with black pile in C. sahlbergi), terga II–IV completely pruinose (lateral margins shiny in C. sahlbergi and C. vangaveri) and sterna III–IV with mainly adpressed yellow pile (laterally with erect pile in C. sahlbergi and C. vangaveri). Etymology This species is named after Janne Ouwehand, the beloved wife of the author of the species, who together with her husband collected the holotype. Species epithet to be treated as a noun in the genitive case. Material examined Holotype GEORGIA•♂;Samegrelo-ZemoSvaneti,Ushguli;42.911°N,42.938°E;2480ma.s.l.;27Jun.2018; S. Bot leg.; ZFMK, SB.003219 = CNC databasing S. Bot 755. Description Male Length. Body 6.5 mm, wing 5.5 mm. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 103 h ead . Face bare, with facial tubercle, black, slightly pruinose, more densely pruinose below lunule. Mala pruinose. Parafacia black, wide, about as wide as postpedicel, pruinose, white pilose. Length of eyecontiguityslightlyshorterthanthelengthoffrons.Angleofapproximationofeyes95°.Frontal triangle black, pruinose, long black pilose, with narrow yellow pile anteriorly, with medial frontal sulcus. Ocellar triangle shiny, long black pilose. Occiput pruinose, with short yellow and long black pile. Lunule black, medial arm on lunule absent, antennal fossa present. Scape and pedicel black with black setae; postpedicel rounded, about as wide as high, basoventrally orange, otherwise black. Arista black, basal quarter thickened, short pilose, longest pilosity half as long as width of arista at base. Eye bare. thorax.Scutumblack,shinyexceptnarrowlyanteriorlyandnotopleuronslightlypruinose,finely punctured, with short erect whitish and sparser long erect black pile. Scutellum black, shiny, anteriorly narrowly pruinose, with short whitish pile and sparse black pile, posterior margin with black setae, length of setae just shorter than length of scutellum. Pleura black, pruinose, with yellow pile, except posterior Fig. 51. Cheilosia (Taeniochilosia) ouwehandae Bot sp.nov.,holotype,♂(ZFMK,SB.003219).A, C. Habitus, lateral and dorsal views; body length 6.5 mm. B. Head, lateral view; eye width 1.0 mm. D. Surstylus, lateral view. E. Postgonite, lateral view. Scale bars: A–C not to scale; D–E in µm. European Journal of Taxonomy 1023: 1–181 (2025) 104 anepisternum with mixed yellow and black pile, dorsal and ventral pile patches on katepisternum widely separated. Haltere with pedicellum yellow, capitulum dark brown to black. Wing. Wing including alula entirely microtrichose; veins black; stigma brown. Legs. Coxae and trochanters black. Femora, tibiae and tarsi black, pruinose. Profemur and mesofemur ventrally and anterolaterally with long mixed yellow and black pile; metafemur ventrally with short yellow pile and some black setae. Tibia with short adpressed yellow and black pile. Tarsi dorsally with black pile, ventrally yellow and black pilose. abdomen. Terga I–IV laterally with long erect yellow pile, in center with short adpressed yellow pile; tergum I pruinose, terga II–III pruinose, in center pruinosity less dense, tergum IV pruinose, most dense pruinosity on anterior part. Sterna I–II with erect yellow pile, sterna III–IV with short adpressed yellow pile, sterna I–IV thickly pruinose. Genitalia with surstylus about twice as long as wide. Dorsal and ventral lobes of postgonite pointed. Female Unknown. Genetics See Remarks under C. aenigmatosa. The DNA barcode of the holotype is placed between two wellsupported clusters of C. aenigmatosa. Biology The holotype was collected just above the tree line in an area with a mixture of extensive grasslands and Rhododendron (Rhododendron sp.) at 2480 m a.s.l. Distribution Only known from the type locality from the Greater Caucasus in Georgia. Cheilosia (Cheilosia) pagana (Meigen, 1822) Fig. 52 Syrphus paganus Meigen, 1822: 292. Cheilosia pagana – Stackelberg & Richter 1968: 247. — Peck 1988: 112. — Barkalov 1993: 712. — Gujabidze 2002: 246. — Barkalov & Mutin 2018: 483. — Mengual et al. 2020: 19. Differential diagnosis Cheilosia pagana is a small (5–9 mm) and slender species. It is characterized by the bare face, narrow parafacia, bare eye, lunule with distinct medial arm, bicoloured legs, posterior margin of scutellum with setae and shiny sterna. The female stands out amongst those of similar looking species by possessing a very large, bright orange postpedicel (Fig. 52D). Material examined Collected in 2018, 2019 and 2023, but 2018 records were not published in Mengual et al. (2020) We report here all the records. GEORGIA – Adjara Region•1♀;KintrishiNatureReserve;41.7433°N,42.0840°E;1235ma.s.l.; 27 Jul.–10 Aug. 2018; GGBC-members leg; ZFMK, ZFMK-TIS-8010465. – Kakheti•1♀;Lagodekhi N.P.;41.8767°N,46.2429°E;615ma.s.l.;2May2023;S.Botleg.;SBA,SB.002716.–Mtskheta- BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 105 Fig. 52. Cheilosia (Cheilosia) pagana (Meigen, 1822). A.♂(FMT);habitus,lateralview;collectedin Georgia; body length 9.1 mm. B.♂(FMT);head,lateralview;collectedinGeorgia;eyewidth1.0mm. C.♂(FMT);habitus,dorsalview;collectedinGeorgia;bodylength7.7mm.D.♀(SBA,SB.002717); head, lateral view; collected in Georgia; eye width 1.2 mm. E.♂(SBA,SB.004458);head,dorsalview; collected in the Netherlands; head width 2.7 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 112 Distribution Caucasus (Armenia, Azerbaijan, Georgia, Russia). Cheilosia (Cheilosia) proxima (Zetterstedt, 1843) Fig. 57 Eristalis proxima Zetterstedt, 1843: 792. Cheilosia proxima – Tóth 1986: 94. — Peck 1988: 114. — Barkalov 1993: 700. — Barkalov & Mutin 2018: 483. — Mengual et al. 2020: 19. Differential diagnosis Cheilosia proxima is a member of a group of closely related species, called the proximagroup(Vujić et al. 2013) in which the pilose eyes, posterior margin of scutellum with setae, usually partly yellow legs, continuously pilose katepisternum, pruinose sterna and the shape of postgonite are distinctive Fig. 56. Cheilosia (Taeniochilosia) pollinifacies Stackelberg, 1968. Collected in Georgia. A.♂(SBA); habitus, lateral view; body length 9.8 mm. B.♂(SBA);habitus,dorsalview;bodylength10.2mm. C.♂(SBA,SB.002729);head,lateralview;eyewidth1.3mm.D.♀(SBA,SB.002745);head,lateral view; eye width 1.3 mm. E.♂(SBA,SB.002734);scutellum,posteriorview;scutellumwidth1.9mm. Not to scale. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 113 Fig. 57. Cheilosia (Cheilosia) proxima (Zetterstedt, 1843). Collected in Georgia. A.♂(FMT,ZFMKTIS-8028470); habitus, lateral view; body length 10.1 mm. B.♂(ZFMK,ZFMK-TIS-8008810);habitus, lateral view; body length 9.2 mm. C.♂(FMT,ZFMK-TIS-8027950);habitus,lateralview;bodylength 7.9 mm. European Journal of Taxonomy 1023: 1–181 (2025) 114 characters. For a full diagnosis of the Cheilosia proximagroupseeVujićet al. (2013). The male genitalia of C. proximaarefiguredinVujićet al. (2013).Within the proxima group, C. proxima is most similar to C. gigantea. For differences, see the Differential diagnosis of C. gigantea. Material examined Collected in 2018, 2019, 2021 and 2023; see Mengual et al. (2020) for detailed records from 2018. Genetics DNA barcodes of C. proxima from the Caucasus appear clustered in three distinct groups with high support (BS = 99.8%; BS = 100%; BS = 100%). Two of these groups comprise only Caucasian individuals and the third has European and Caucasian specimens. For each group a male is portrayed in Fig. 57 A–C. Remarks Specimens from all three distinctly different barcoding groups are also morphologically distinct, they often occurred at different locations, habitats and times of the year, and they could represent three distinct species. However, when testing these groups morphologically against European material, European specimens show a wide variation with intermediate looking specimens. Due to the lack of extensive genetic samples in Europe it remains unknown if the variation found in European specimens of C. proxima might be correlated with some genetic difference as well or not. More molecular data is neededtoproperlyassesstheintraspecificandinterspecificvariabilityofthisveryvariableandwideranging species. Biology During our expeditions, collected between 4 May and 8 July at an altitude between 1090 and 2700 m a.s.l. A species found in meadows and clearings near forest in the lower montane zone to alpine meadows above the treeline, but phenology and habitat (elevation niche) differ between the barcoding clusters. Distribution Palaearctic. Cheilosia (Cheilosia) pseudogrossa Stackelberg, 1968 Fig. 58 Cheilosia pseudogrossa Stackelberg, 1968: 228. Cheilosia pseudogrossa – Stackelberg & Richter 1968: 248. — Stackelberg 1970: 59. — Barkalov 1993: 714. — Barkalov & Mutin 2018: 483. — Mengual et al. 2020: 20. Cheilosia pseudogrossa Stackelberg, 1956 [sic] — Gujabidze 2002: 246. Differential diagnosis Cheilosia pseudogrossa is genetically and morphologically very similar to C. grossa. It can however easilybeidentifiedfromitbythepiloseface(bareinC. grossa). Other differences in the male (we could not study the female) include the postpedicel being dark orange to brown (black in C. grossa), face ventrolateral of facial tubercle not swollen (swollen in C. grossa), pile on anepimeron with straight apex (with wavy apex in C. grossa) and terga III–IV pruinose (lateral sides of tergum III widely shiny and tergum IV entirely shiny except anterior margin in C. grossa). BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 115 Material examined Not collected in 2018, but collected in 2023. GEORGIA – Mtskheta-Mtianeti•1♂;Lutkhubi;42.3984°N,44.7996°E;2068ma.s.l.;8May 2023;S.Botleg.;SBA,SB.003236=ZFMK-TIS-8027992•1♂;Lutkhubi;42.4006°N,44.7956°E; 2130 m a.s.l.; 8 May 2023; F. Van de Meutter leg.; FMT, ZFMK-TIS-8027940 . Fig. 58. Cheilosia (Cheilosia) pseudogrossa Stackelberg, 1968. Collected in Georgia. A.♂(SBA, ZFMK-TIS-8027992); habitus, lateral view; body length 13.4 mm. B.♂(FMT,ZFMK-TIS-8027940); head, lateral view; eye width 1.5 mm. C.♂(SBA,ZFMK-TIS-8027992);habitus,dorsalview;body length 13.4 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 116 Genetics The two DNA sequences of C. pseudogrossa cluster together with high support (BS = 99.7%) in our NJ tree. See Genetics under C. grossa. Biology Duringourexpeditions,collectedon8Mayatanaltitudebetween2068and2130ma.s.l.onflowering willow Salix sp. Distribution Caucasus (Abkhazia region, Georgia, Russia). Cheilosia (Cheilosia) psilophthalma Becker, 1894 Fig. 59 Chilosia psilophthalma Becker, 1894: 495. Differential diagnosis Cheilosia psilophthalma is very similar to C. urbana, the latter which is very common throughout the Caucasus. The male of C. psilophthalma is distinguishable from that of C. urbana by the shape of the dorsal lobe of the postgonite (short and triangular in C. psilophthalma and narrow and long in C. urbana, for drawings of the male genitalia of both species see Claussen & Doczkal 1998) and by the frons (slightly swollen in C. psilophthalma but not swollen in C. urbana). More differences with C. urbana, which are true for both sexes, include the black claws (claw base orange in C. urbana), slightly pruinose sterna (true for Caucasian specimens, in Europe shiny in both species) (sterna shiny in C. urbana), wider parafacia and postpedicel orange and rounded (postpedicel dark orange to dark brown and wider than high in C. urbana). In the female, the frons is wider than in that of C. urbana. Material examined Cheilosia psilophthalma was not collected in 2018, but collected in 2023. GEORGIA – Mtskheta-Mtianeti•1♀;Lutkhubi;42.3867°N,44.79°E;1580ma.s.l.;6May2023; F. Van de Meutter leg.; FMT, ZFMK-TIS-8028472. – Samtskhe-Javakheti•1♂;Sakire,41.7301°N, 43.3306°E;1820ma.s.l.;10May2023;F.VandeMeutterleg.;FMT,ZFMK-TIS-8028471. Genetics DNA barcodes of C. psilophthalma from Europe and Caucasus cluster together with high support (BS = 100%). Remarks ReportedfromtheCaucasusforthefirsttime. Biology During our expeditions, collected between 6 May and 10 May at an altitude between 1580 and 1820 m a.s.l. Present in both the Greater and Lesser Caucasus. Distribution Europe, European parts of Russia, Caucasus (Georgia). BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 117 Fig. 59. Cheilosia (Cheilosia) psilophthalma Becker, 1894. Collected in Georgia. A–D.♂(FMT,ZFMKTIS-8028471); body length 7.6 mm. A. Habitus, lateral view. B. Head, lateral view; eye width 1.1 mm. C. Habitus, dorsal view. D. ♂(FMT,ZFMK-TIS-8028471);head,frontalview;headwidth2.4mm. E.♀ (FMT, ZFMK-TIS-8028472); head, lateral view; eye width 1.0 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 118 Cheilosia (Cheilosia) rediVujić,1996 Fig. 60 Cheilosia melanopa rediVujić,1996:93. Cheilosia melanopa (Zetterstedt, 1843) – Mengual et al. 2020: 18 (part, see Remarks). Differential diagnosis The male of Cheilosia redi is distinguishable from those of all other Cheilosia except C. borjomi sp. nov., C. lasiopa, C. variabilis and C. melanopa by the combination of pilose face, pruinose scutum and sickle-shaped dorsal lobe of the postgonite. The male can be distinguished from that of C. lasiopa by, amongst other characters, longer setae on posterior margin of scutellum, shorter sickle-shaped dorsal lobe of postgonite and longer pile on metafemur. The male genitalia of C. rediarefiguredinFrancuski et al. (2009). The male of C. redi differs from those of C. borjomi and C. variabilis by, amongst other characters, smaller body size (8–11 mm vs 10–12 mm), stockier abdomen, tibiae usually narrowly yellow at base and apex (usually all black in C. borjomi and C. variabilis), absence of black setae on ventral part of metafemur (present in C. borjomi and C. variabilis), and yellow pile on entire posterior part of metatibia, (basal half of metatibia with black pile in C. borjomi and C. variabilis). The male of C. redi is very similar to that of C. melanopa, but it differs by the short pilosity on arista, at the base of arista about half as long as diameter of arista at base (in C. melanopa the aristal pile at base almost as long as diameter of arista at base), long pile on occiput behind dorsal margin of eyes partly yellow (Fig. 60E) (entirely black pilose in C. melanopa), metafemur with at least basal 60% of the anterior long and short pile yellow (at most the basal third metafemur yellow pilose in C. melanopa), metatibia posteriorly with yellow pile entirely (in C. melanopa only apical half of metatibia with yellow pile posteriorly, basal half with black pile). In general, the male of C. redi is has more yellow pilosity: face with predominantly yellow instead of predominantly black pile, scutum with larger proportion of yellow pile, dorsal pile of katepisternum yellow (almost always with some black pile intermixed in C. melanopa) and terga II–IV entirely or almost entirely with yellow pile (in C. melanopa almost always with black pile medially in posterior part); on average the male of C. redi has paler legs: usually protibia and mesotibia with yellow base and apex (Fig. 60A), while in C. melanopa legs often entirely black or only base yellow or pale parts dark orange. The female of C. redi is similar to that of C. melanopa but the metatibia is entirely yellow pilose (in C. melanopa the anterior side of metatibia with black pile), terga II–IV medially with yellow pile only, sometimes shorter black pile present (in C. melanopa terga II–IV always with distinct adpressed black pile, at least posteriorly). Female of C. redi has on average more yellow legs, more often protibia and mesotibia yellow at both ends and with yellow long pile on the dorsal margin of occiput behind dorsal margin of eyes (Fig. 60F) (often black in C. melanopa). The female of C. redi is very similar to the female of C. pogonias sp. nov., for differences see Differential diagnosis under C. pogonias. Material examined Collected in 2018, 2019, 2022 and 2023, but 2018 records were not published in Mengual et al. (2020). Thus, all our records are reported here. GEORGIA – Adjara Region•1♀;KintrishiNatureReserve;41.7293°N,42.0775°E;1035ma.s.l.; 20Apr.–5May2018;GGBC-membersleg;ZFMK,ZFMK-TIS-8010448•1♀;KintrishiNature Reserve;41.7433°N,42.0840°E;1235ma.s.l.;7–20May2018;GGBC-membersleg;ZFMK, ZFMK-TIS-8010480•1♂;KintrishiNatureReserve;41.7551°N,42.1124°E;2268ma.s.l.;2–16 Jun.2018;GGBC-membersleg;ZFMK,ZFMK-TIS-8010565•1♀;KintrishiNatureReserve; 41.7553°N,42.1129°E;2280ma.s.l.;2–16Jun.2018;GGBC-membersleg;ZFMK,ZFMK- BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 119 Fig. 60. Cheilosia (Cheilosia) redi Vujić,1996.CollectedinGeorgia.A–B.♂(ZFMK);habitus,lateral and dorsal views; body length 9.8 mm. C–D.♀(ZFMK,ZFMK-DIP-00066251);habitus,lateraland dorsal views; body length 9.3 mm. E.♂(ZFMK);head,lateralview;eyewidth1.4mm.F.♀(ZFMK, ZFMK-DIP-00066251); head, lateral view; eye width 1.4 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 120 TIS-8010543•1♀;KintrishiNatureReserve;41.7553°N,42.1128°E;2280ma.s.l.;2–16Jun.2018; GGBC-membersleg;ZFMK,ZFMK-TIS-8010556•1♂;KintrishiNatureReserve;41.7619°N, 42.1162°E;2462ma.s.l.;16–30Jun.2018;GGBC-membersleg;ZFMK,ZFMK-TIS-8010535• 1♀;KintrishiNatureReserve;41.7619°N,42.1162°E;2462ma.s.l.;30Jun.–14Jul.2018;GGBCmembers leg; ZFMK, ZFMK-TIS-8002723. – Kakheti•1♀;BatsaraNatureReserve,Rangersoffice; 42.22246°N,45.30369°E;807ma.s.l.;28–29May2022;X.Mengualleg.;Malaisetrap;ZFMK, ZFMK-DIP-00094242. – Mtskheta-Mtianeti•1♀;TbilisiN.P.;41.8808°N,45.0203°E;1270ma.s.l.; 1Jun.2022;X.Mengualleg.;ZFMK,ZFMK-DIP-00094160=ZFMK-TIS-8014609•2♀♀;Tbilisi N.P.;41.8808°N,45.0203°E;1270ma.s.l.;27May2022;X.Mengual leg.;ZFMK,ZFMKDIP-00093899=ZFMK-TIS-8014608,ZFMK-DIP-00093893=ZFMK-TIS-8014606•21♀♀;Tbilisi N.P.;41.88116°N,45.020803°E;1275ma.s.l.;27May–1Jun.2022;X.Mengualleg.;Malaisetrap; ZFMK, ZFMK-DIP-00094263 to ZFMK-DIP-00094265, ZFMK-DIP-00094269, ZFMK-DIP-00094275, ZFMK-DIP-00094308, ZFMK-DIP-00094326, ZFMK-DIP-00094377 to ZFMK-DIP-00094380, ZFMK-DIP-00094446, ZFMK-DIP-00094447, ZFMK-DIP-00094452, ZFMK-DIP-00094453, ZFMKDIP-00094456,ZFMK-DIP-00094459,ZFMK-DIP-00094461toZFMK-DIP-00094464•1♀;Tbilisi N.P.;41.880°N,45.023°E;1289ma.s.l.;4May2023;S.Botleg.;SBA,SB.003049•2♀♀;same dataasforpreceding;L.Hofsteeleg.;LHH•3♀♀;TbilisiN.P.;41.877°N,45.0138°E;1250ma.s.l.; 4May2023;F.VandeMeutterleg.;FMT•1♂;TbilisiN.P.;41.8802°N,45.0220°E;1279ma.s.l.; 4May2023;W.Opdekampleg.;WOR,A005•2♀♀;samedataasforpreceding;WOR,A004,A014 •1♂;Lutkhubi;42.3797°N,44.7969°E;1463ma.s.l.;6May2023;S.Botleg.;SBA,SB.003050• 2♀♀;samedataasforpreceding;SBA,SB.003051,SB.003052•1♀;samedataasforpreceding; ZFMK,ZFMK-TIS-8027974•1♀;Lutkhubi;42.3797°N,44.7969°E;1463ma.s.l.;6May2023; L.Hofsteeleg.;LHH•4♂♂,3♀♀;Lutkhubi;42.3867°N,44.79°E;1580ma.s.l.;6May2023; F.VandeMeutterleg.;FMT•10♂♂;Lutkhubi;42.3951°N,44.7847°E;2138ma.s.l.;6May2023; F.VandeMeutterleg.;FMT•2♂♂;Lutkhubi;42.3930°N,44.7929°E;1700ma.s.l.;6May2023; W.Opdekampleg.;WOR,A002,A011•5♂♂;Lutkhubi;42.3823°N,44.7856°E;1500ma.s.l.;6May 2023;W.Opdekampleg.;WOR,D001,D004,D015,D018,D019•1♀;samedataasforpreceding; D032•3♂♂;Lutkhubi;42.3938°N,44.7857°E;2120ma.s.l.;6May2023;W.Opdekampleg.; WOR,E004,E020,E021•6♂♂,7♀♀;Lutkhubi;42.3936°N,44.7923°E;1760ma.s.l.;8May2023; F.VandeMeutterleg.;FMT•1♂;Lutkhubi;42.3930°N,44.7929°E;1734ma.s.l.;8May2023; W.Opdekampleg.;WOR,C025•1♀;TbilisiN.P.;41.8787°N,45.0288°E;1316ma.s.l.;9May 2023;S.Botleg.;SBA,SB.003055•2♀♀;TbilisiN.P.;41.8770°N,45.0137°E;1248ma.s.l.;9May 2023; S. Bot leg.; SBA, SB.003053, SB.003054. – Racha-Lechkhumi and Kvemo Svaneti•1♀; Tsana;42.90°N,43.14°E;1830ma.s.l.;18Jun.2019;J.vanSteenisleg.;JSB,2019-00.861•1♀; Tsana;42.9089°N,43.1425°E;1900ma.s.l.;19Jun.2019;F.VandeMeutterleg.;FMT•3♀♀; 42.82111°N,43.16069°E;1450ma.s.l.;20Jun.2019;X.Mengualleg.;ZFMK,ZFMK-TIS-8006797= ZFMK-DIP-00066232,ZFMK-TIS-8006817=ZFMK-DIP-00066233,ZFMK-DIP-00066195•2♀♀; 42.82°N,43.16°E;1485ma.s.l.;20Jun.2019;J.vanSteenisleg.;JSB,2019-00.862,2019-00.863.– Samegrelo-Zemo Svaneti•1♀;42.912°N,42.937°E;2430ma.s.l.;27Jun.2018;S.Botleg.;SBA, SB.003046•1♀;Mestia;43.0256°N,42.8908°E;2550ma.s.l.;13Jun.2019;F.VandeMeutterleg.; FMT•1♂;UghviriLake;43.0319°N,42.8272°E;1905ma.s.l.;13Jun.2019;X.Mengualleg.;ZFMK, ZFMK-TIS-8006798=ZFMK-DIP-00066231•1♀;43.02836°N,42.87878°E;2345ma.s.l.;13Jun. 2019;X.Mengualleg.;ZFMK,ZFMK-TIS-8006799=ZFMK-DIP-00066251•1♀;Mestia;43.042°N, 42.768°E;1473ma.s.l.;13Jun.2019;S.Botleg.;SBA,SB.003047=CNCdatabasingS.Bot933• 1♀;Mestia;43.02°N,42.87°E;2350ma.s.l.;13Jun.2019;J.vanSteenisleg.;JSB,2019-00.880• 1♀;42.9989°N,42.6501°E;1273ma.s.l.;13–14Jun.2019;X.Mengualleg.;Malaisetrap;ZFMK, ZFMK-DIP-00078704=ZFMK-TIS-8010113•1♀;43.112°N,42.743°E;1713ma.s.l.;14Jun.2019; L.Hofsteeleg.;LHH•1♀;Ushguli;42.920°N,42.937°E;2283ma.s.l.;16Jun.2019;L.Hofsteeleg.; LHH•1♀;Ushguli;42.920°N,42.937°E;2283ma.s.l.;17Jun.2019;S.Botleg.;SBA,SB.003048= CNCdatabasingS.Bot934•1♂;Ushguli;42.898°N,43.008°E;2601ma.s.l.;18Jun.2019;S.Bot BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 121 leg.; SBA, SB.003044. – Samtskhe-Javakheti•1♀;BorjomiN.P.;41.867°N,43.251°E;2000ma.s.l.; 18Jun.2018;S.Botleg.;SBA,SB.003045•1♂;BorjomiN.P.;41.824°N,42.848°E;2165ma.s.l.; 10Jun.2019;S.Botleg.;SBA,SB.003043•1♀;41.8234°N,42.8400°E;2025ma.s.l.;11Jun.2019; X. Mengual leg.; ZFMK, ZFMK-DIP-00066336. Genetics There is a cluster (BS = 91.2%) in our NJ tree with C. redi and C. melanopa barcodes. All DNA barcodes of C. redi are clustered together with high support value (BS = 100%) and all DNA sequences of C. melanopa as well (BS = 98.1%). Remarks ReportedfromtheCaucasus,andGeorgia,forthefirsttime.Barkalov(1993)alreadywrotethat C. melanopa was polymorphic, with one morph having almost black legs and black pilosity on scutum and scutellum, and a second pale morph with legs partly yellow and mostly yellow pilosity on scutum and scutellum. The pale morph, very likely, is C. redi. Some records of C. melanopa in Mengual et al. (2020) actually are C. redi, and are reported here again as C. redi. Biology Collected in mountains between 1248–2601 m a.s.l. between 4 May and 20 June. It can be found in sympatry with C. melanopa. Found in the montane and subalpine zone near forest and in forest clearings as well as on alpine meadows. Distribution Within Europe, occurs mainly in the Balkan Peninsula with scattered records in Central Europe. Caucasus (Georgia). Cheilosia (Cheilosia) rhynchops Egger, 1860 Fig. 61 Cheilosia rhynchops Egger, 1860: 353. Cheilosia rhynchops – Barkalov 1993: 699. — Barkalov & Mutin 2018: 484. — Mengual et al. 2020: 20. Differential diagnosis Cheilosia rhynchops is characterized by the combination of a bare face, pilose eye, black legs, posterior margin of scutellum with setae and shiny sterna. In the Caucasus it can be mainly confused with C. caucasi sp. nov. but it has an elongated face (Fig. 61B, D, with long straight part between antennae and facial tubercle (in C. caucasi sp. nov. face not elongated) and the dorsal and ventral pile patches on the katepisternum are connected or almost so in the Caucasian populations (widely separated in C. caucasi). In the male the frons is swollen (not swollen in C. caucasi) and scutum with long black and white pile (scutum usually with mainly black pile in C. caucasi). In the female scutum with adpressed mainly golden pile (variable in C. caucasi) and postpedicel dark orange in basoventral corner (black in C. caucasi). Material examined Collected in 2018, 2019 and 2023; see Mengual et al. (2020) for detailed records from 2018. European Journal of Taxonomy 1023: 1–181 (2025) 128 41.7144°N,46.0531°E;215ma.s.l.;2May2023;F.VandeMeutterleg.;FMT•1♀;DedoplisTskaro; 41.4848°N,46.0947°E;750ma.s.l.;5May2023;S.Botleg.;SBA,SB.002800•1♂;Heretiskari; 41.7125°N,46.0515°E;220ma.s.l.;5May2023;W.Opdekampleg.;WOR,B006.–Kvemo Kartli •2♂♂;GardabaniMonastery;41.8341°N, 44.8762°E;600ma.s.l.;9May2023;W.Opdekampleg.; WOR, A003, A002. – Mtskheta-Mtianeti•1♀;Saguramo;41.89°N,44.75°E;550ma.s.l.;21Jun. 2019;J.vanSteenisleg.;JSB,2019-00.836•1♂;41.8811°N,45.0206°E;1251ma.s.l.;22Jun.2019; S.Botleg.;SBA,SB.002814•1♂;TbilisiNationalPark;41.8808°N,45.0204°E;1270ma.s.l.;22Jun. 2019;X.Mengualleg.;ZFMK,ZFMK-DIP-00066225•2♀♀;samedataasforpreceding;ZFMK, ZFMK-DIP-00066200=ZFMK-TIS-8006803,ZFMK-DIP-00066201=ZFMK-TIS-8006804•1♀; samedataasforpreceding;F.VandeMeutterleg.;FMT•1♀;Mtskheta-Mtianeti,TbilisiNationalPark; 41.8784°N,45.016°E;1249ma.s.l.;22Jun.2019;J.H.Skevingtonleg.;CNC1392958;CNC.–Tbilisi •3♂♂;Mamkoda;41.8339°N,44.8763°E;920ma.s.l.;9May2023;F.VandeMeutterleg.;FMT Genetics DNA barcodes of C. ruffipes from Europe and Caucasus cluster together with high support (BS = 99.9%). Fig. 64. Cheilosia (Eucartosyrphus) ruffipes (Preyssler, 1793). Collected in Georgia. A.♂(SBA, SB.002804); habitus, lateral view; body length 8.9 mm. B.♂(SBA,SB.002811);head,lateralview; eye width 1.1 mm. C.♂(SBA,SB.002811);habitus,dorsalview;bodylength9.8mm.D.♀(SBA, SB.002806); head, lateral view; eye width 1.2 mm. Not to scale. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 129 Remarks This species appears in recent literature with the name C. soror; but see Mengual et al. (2020). Biology During our expeditions, collected between 30 April and 1 July at an altitude between 301 and 1251ma.s.l.Occursinorneardryforests.Isoftenfoundonumbelliferflowers. Distribution Palaearctic. Within the Caucasus reported from Armenia, Georgia and Russia. Cheilosia (Cheilosia) schnabli Becker, 1894 Fig. 65 Chilosia schnabli Becker, 1894: 498. Fig. 65. Cheilosia (Cheilosia) schnabli Becker, 1894. Collected in Georgia. A.♂(SBA);habitus,lateral view; body length 9.2 mm. B.♂(SBA);head,lateralview;eyewidth1.4mm.C.♂(SBA);habitus, dorsal view; body length 8.9 mm. D.♀(SBA,SB.002794);head,lateralview;eyewidth1.3mm.Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 130 Chilosia schnabli – Stackelberg & Richter 1968: 248. — Stackelberg 1970: 61. — Peck 1988: 116. — Barkalov 1993: 726. — Mengual et al. 2020: 20. — Speight 2020a: 50. Cheilosia schnabli Becker, 1921 [sic] – Gujabidze 2002: 246. Differential diagnosis Cheilosia schnabli is very similar to C. inarmata sp. nov. For a diagnosis, see the Differential diagnosis under C. inarmata. For differences with the extralimital C. impressa, and for drawings of the male genitalia,seeVujićet al. (1998). Material examined Collected in 2018, 2019, 2021, 2022 and 2023; see Mengual et al. (2020) for detailed records from 2018. Genetics All DNA barcodes of C. schnabli cluster together with a relatively high support (BS = 94.7%). Moreover, we recovered a cluster with high support (BS = 99.7%) with some COI sequences of the C. transcaucasica (BS = 100%) and those of C. schnabli. Biology During our expeditions, collected between 4 May and 24 July at an altitude between 1250 and 1969 m a.s.l. Distribution Balkan Peninsula, Caucasus (Armenia, Georgia, Russia), Kazakhstan. Cheilosia (Eucartosyrphus) scutellata (Fallén, 1817) Fig. 66 Eristalis scutellata Fallén, 1817: 55. Cheilosia scutellata – Stackelberg & Richter 1968: 248. — Stackelberg 1970: 58, — Peck 1988: 116. — Barkalov 1993: 712. — Gujabidze 2002: 245. — Barkalov & Mutin 2018: 485. — Mengual et al. 2020: 23. Differential diagnosis Cheilosia scutellata shares the following set of characters only with the very similar C. ruffipes: face and eye bare; arista long pilose (pile longer than width of arista at base) and facial tubercle broad, semicircular in dorsal view. It can always be separated from C. ruffipes by the bare posterodorsal corner of the anterior anepisternum (pilose in C. ruffipes), and colour of the postpedicel ranging from dark orange to dark brown (Fig. 66B, D) (bright orange in C. ruffipes). Material examined Collected in 2018, 2019, 2021, 2022 and 2023; see Mengual et al. (2020) for detailed records from 2018. Genetics European and Caucasian DNA barcodes of C. scutellata group together in our NJ tree with high support (BS = 98.7%). BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 131 Biology During our expeditions, collected between 12 May and 3 August at an altitude between 1090 and 2022ma.s.l.Isoftenfoundinornearforestandfeedsonumbelliferflowers. Distribution Palaearctic. Within the Caucasus known from Armenia, Georgia and Russia. Fig. 66. Cheilosia (Eucartosyrphus) scutellata (Fallén, 1817). A, C.♂(SBA,SB.002823),collectedin Georgia;. A. Habitus, lateral view; body length 9.8 mm. B.♂(SBA,SB.002817);head,lateralview; collected in Georgia; eye width 1.2 mm. C. Habitus, dorsal view; collected in Georgia; body length 9.8 mm. D.♀(SBA,SB.002815);head,lateralview;collectedinGeorgia;eyewidth1.1mm.E.♂ (SBA, SB.004477); head, dorsal view; collected in the Netherlands; head width 2.9 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 132 Cheilosia (Pollinocheila) semifasciata Becker, 1894 Fig. 67 Chilosia semifasciata Becker, 1894: 443. Chilosia semifasciata – Barkalov 1993: 699. — Barkalov & Mutin 2018: 486. Fig. 67. Cheilosia (Pollinocheila) semifasciata Becker, 1894. A.♂(ASW,ZFMK-TIS-8008774); habitus, lateral view; collected in Georgia; body length 7.2 mm. B.♂(ASW,ZFMK-TIS-8008774); head, lateral view; collected in Georgia; eye width 0.9 mm. C.♂(ASW,ZFMK-TIS-8008774);habitus, dorsal view; collected in Georgia; body length 7.2 mm. D.♀(SBA,SB.004484);head,lateralview; collected in the Netherlands; eye width 0.8 mm. Not to scale. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 133 Differential diagnosis Cheilosia semifasciata is characterized by the combination of bare face, bare eye, at least base of tibiae yellow, posterior margin of scutellum with setae and ventral and dorsal pile patches on katepisternum widelyseparated.EasilymisidentifiedbecauseofinconclusivepatternonSternaII–IV,notbeing uniformly shiny nor pruinose: on anterior part distinctly pruinose, on posterior part usually shiny. Males can be distinguished from similar species by the distinct pruinose spots on the abdomen (two large grey pruinosespotsontergaII–IV)andthefemalesbythescutumwitherectgoldenpile.Foridentification from similar but extralimital C. fasciata Schiner & Egger, 1853, see Bot & Van de Meutter (2023). Material examined Not collected in 2018, but collected in 2019. GEORGIA•1♂,Samegrelo-ZemoSvaneti;43.1166°N,42.7276°E;1850ma.s.l.;14Jun.2019; X. Mengual leg.; ZFMK, ZFMK-DIP-00066393 = ZFMK-TIS-8008774. Genetics COI sequences of C. semifasciata from Europe and Caucasus cluster together with high support (BS = 100%). Remarks Barkalov (1993) reported a single female of C. semifasciata collected in Lars, a small town in the RepublicofNorthOssetia-Alania.Thus,ourrecordisthefirstforGeorgia. Distribution Europe, Caucasus (Georgia, Russia). Cheilosia (Montanocheila) subpictipennis Claussen, 1998 Fig. 68 Cheilosia subpictipennis Claussen, 1998: 405. Differential diagnosis Cheilosia subpictipennis belongs to the subgenus Montanocheila and is very similar to the sympatric occurring Cheilosia rufa sp. nov. For differences, see the Differential diagnosis under Cheilosia rufa sp. nov. For diagnostic characteristics of C. subpictipennis from other European species of Montanocheila,andforfiguresofthemalegenitalia,seeClaussen(1998). Material examined Cheilosia subpictipennis was not collected in 2018, but collected in 2019 and 2023. GEORGIA – Mtskheta-Mtianeti•1♂;Lutkhubi;42.3797°N,44.7969°E;1463ma.s.l.;6May2023;S. Botleg.;SBA,SB.002832=ZFMK-TIS-8027977•1♂;Lutkhubi;42.3930°N,44.7929°E;1700ma.s.l.; 6May2023;W.Opdekampleg.;WOR,A019=ZFMK-TIS-8028486•1♂;Lutkhubi;42.3888°N, 44.7915°E;1624ma.s.l.;8May2023;S.Botleg.;SBA,SB.002833=ZFMK-TIS-8027969•1♀;same dataasforpreceding;SBA,SB.002834=ZFMK-TIS-8027970•1♂;Lutkhubi;42.3930°N,44.7929°E; 1734 m a.s.l.; 8 May 2023; W. Opdekamp leg.; WOR, C019. – Samtskhe-Javakheti•1♀;BorjomiN.P.; 41.823°N,42.841°E;2049ma.s.l.;11Jun.2019;S.Botleg.;SBA,SB.002835=ZFMK-TIS-8010570. Genetics DNA barcodes of C. subpictipennis from Europe and Georgia cluster together with high support (BS = 100%). European Journal of Taxonomy 1023: 1–181 (2025) 134 Remarks SpeciesreportedfromtheCaucasusandfromGeorgiaforthefirsttime. Biology During our expeditions, collected between 6 May and 11 June at an altitude between 1463 and 2049 m a.s.l. Almost all specimens were caught on willow Salix sp. catkins. Distribution Europe, Western Siberia, Caucasus (Georgia). Fig. 68. Cheilosia (Montanocheila) subpictipennis Claussen, 1998. Collected in Georgia. A.♂(WOR, ZFMK-TIS-8028486); habitus, lateral view; body length 12.5 mm. B.♂(SBA,SB.002833);head,lateral view; eye width 1.5 mm. C.♂(SBA,SB.002832);habitus,dorsalview;bodylength12.5mm.D.♀ (SBA, ZFMK-TIS-8010570); head, lateral view; eye width 1.5 mm. E.♂(SBA);postgonite,lateralview. Scale bar: A–D not to scale; E in µm. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 135 Cheilosia (Cheilosia) teberdensis Barkalov, 1993 Fig. 69 Cheilosia teberdensis Barkalov, 1993: 705. Cheilosia teberdensis – Barkalov & Mutin 2018: 484. — Mengual et al. 2020: 21. Fig. 69. Cheilosia (Cheilosia) teberdensis Barkalov, 1993. Collected in Georgia. A.♂(SBA,SB.002841); habitus, lateral view; body length 10.3 mm. B.♂(SBA,SB.002838);head,lateralview;eyewidth 1.4 mm. C.♂(SBA,SB.002839);habitus,dorsalview;bodylength9.5mm.D.♀(SBA,SB.002837); head, lateral view; eye width 1.4 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 136 Differential diagnosis Cheilosia teberdensis is a member of a group of closely related species, called the proximagroup(Vujić et al. 2013) in which the pilose eyes, posterior margin of scutellum with setae, usually partly yellow legs, continuously pilose katepisternum, pruinose sterna and the shape of postgonite are distinctive characters. For a full diagnosis of the Cheilosia proximagroup,seeVujićet al. (2013). Cheilosia teberdensis stands out, together with C. paragigantea, from other members of the proxima group occurring in the Caucasus by having black legs (tibiae yellow at both ends in the other species). Similar to C. paragigantea; for differences, see Differential diagnosis of that species. Material examined Collected in 2018, 2019, 2021 and 2022; see Mengual et al. (2020) for detailed records from 2018. ARMENIA – Syunik Province•1♂;Spandaryan,smallriver;39.621045° N,45.910242° E; 1986 m a.s.l.; 19 May 2022; X. Mengual leg.; ZFMK, ZFMK-DIP-00093159 = ZFMK-TIS-8014613. Genetics DNA barcodes of C. teberdensis cluster together with high support (BS = 98.6%). Remarks SpeciesreportedfromArmeniaforthefirsttime. Biology During our expeditions, collected between 19 May and 14 July at an altitude between 1463 and 2887 m a.s.l. Distribution Caucasus (Armenia, Georgia, Northern Caucasus). Cheilosia (Cheilosia) transcaucasica Stackelberg, 1960 Fig. 70 Cheilosia transcaucasica Stackelberg, 1960: 440. Cheilosia transcaucasica – Stackelberg & Richter 1968: 249. — Stackelberg 1970: 59. — Peck 1988: 118. — Barkalov 1993: 714. — Barkalov & Mutin 2018: 484. — Mengual et al. 2020: 21. Cheilosia transcaucasika Stackelberg, 1956 [sic] – Gujabidze 2002: 246. Differential diagnosis Cheilosia transcaucasica has a pilose face, pilose eye, black legs, posterior margin of scutellum with setae and sterna pruinose. It stands out amongst Cheilosia species with the same set of characters by the yellow wing base (Fig. 70C), brown or black in the other species. Genetically similar to Cheilosia inarmata sp. nov., but that species has the face bare (pilose in C. transcaucasica). Material examined Collected in 2018, 2019 and 2021; see Mengual et al. (2020) for detailed records from 2018. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 137 Genetics DNA barcodes of C. transcaucasica are grouped together with high support (BS = 100%), with the exception of three specimens from Georgia (ZFMK-TIS-8002801, ZFMK-TIS-8002826, ZFMKTIS-8009526) that share the COI haplotype with C. inarmata sp. nov. Remarks Stackelberg (1960) described the species based on material from Armenia and Azerbaijan, and Stackelberg & Richter (1968) reported material from Armenia, Georgia and Northern Caucasus. Barkalov (1993) stated that this species is found in the entire Caucasus, and later, Barkalov & Mutin (2018) listed it from Northern Caucasus and Iran. Khaghaninia et al. (2012) and Khaghaninia & Kazerani (2014) Fig. 70. Cheilosia (Cheilosia) transcaucasica Stackelberg, 1960. Collected in Georgia. A.♂(SBA, SB.002850); habitus, lateral view; body length 9.3 mm. B.♂(SBA,SB.002844);head,lateralview; eye width 1.3 mm. C.♂(SBA,SB.002850);habitus,dorsalview;bodylength9.3mm.D.♀(SBA, SB.002856); head, lateral view; eye width 1.4 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 144 abdomen.TergaI–IVwithlong,fine,erectyellowpile,rarelyposteriormarginoftergumIVwitha few black pile; tergum I pruinose; terga II–III laterally shiny, medially pruinose, tergum IV pruinose on anterior half to quarter. Sterna I–IV thickly and completely pruinose, with erect yellow pile, adpressed medially on sterna III–IV. Hypopygium pruinose, with yellow pile. Genitalia with surstylus ca 1.4 times as long as wide; dorsal lobe of postgonite narrow basally, long and pointed without a clear hook near the top. Female Length. Body 8.7–9 mm, wing 7.2–7.5 mm. Similar to the male, except for normal sexual dimorphism and the following characters. Frons with yellow pile except a few black pile around ocellar triangle. Postpedicel rarely basally reddish. Pile on scutum and pleura golden yellow, rarely a few black pile on posterior anepisternum, post-alar calli and near wing base. Terga with erect yellow pile at the sides, adpressed in the middle. Tergum I pruinose. Tergum II laterally shiny, medially pruinose, terga III–IV shiny, except for a small area along the anterior margin of tergum III, which is pruinose. Genetics All DNA sequences of C. ushguliensis sp. nov. group together in our NJ tree with high support (BS = 99.4%). Biology Collected between 1900–2615 m a.s.l. on extensive grasslands and in lush vegetation along roadsides. Distribution Only known from the Greater Caucasus in Georgia. Cheilosia (Cheilosia) uviformis Becker, 1894 Fig. 74 Chilosia uviformis Becker, 1894: 499. Differential diagnosis Cheilosia uviformisisdifficulttoidentify,mainlybecauseitisinconclusiveintwocharactersoftenused intheidentificationofCheilosia: the sterna are only slightly pruinose, which could be interpreted as either pruinose or shiny, and in the female the eye is sparsely pilose, which could easily be missed and consequently, the eye pilosity could be interpreted as either bare or pilose (the eye is distinctly pilose in the male). It is very similar to C. psilophthalma, whose Caucasian population also has slightly pruinose sterna. It is distinguishable from C. psilophthalma by bicoloured claws with orange base and black apex (claws all black in C. psilophthalma); the male by densely pruinose frons (shiny or indistinctly pruinose in that of C. psilophthalma) and narrow parafacia, about half as wide as width of postpedicel (about 0.8 times as wide as width of postpedicel in C. psilophthalma) and the female by sparse pilose eye (with distinct pile in that of C. psilophthalma). For differences with other species of Cheilosia, see Bot & Van de Meutter (2023). Material examined Cheilosia uviformis was not collected in 2018, but collected in 2019. GEORGIA – Racha-Lechkhumi and Kvemo Svaneti•1♂;42.9150°N,43.1430°E;1969ma.s.l.; 19Jun.2019;S.Botleg.;SBA,SB.002942•1♂;42.9160°N,43.1428°E;1975ma.s.l.;19Jun. 2019;X.Mengualleg.;ZFMK,ZFMK-DIP-00066504•4♂♂;Tsana;42.9089°N,43.1425°E; BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 145 1900 m a.s.l.; 19 Jun. 2019 F. Van de Meutter leg.; FMT. – Samegrelo-Zemo Svaneti•1♂;43.1133°N, 42.7378°E;1800ma.s.l.;14Jun.2019;X.Mengualleg.;ZFMK,ZFMK-DIP-00066507=ZFMKTIS-8008814•3♂♂,1♀;Ushguli;42.9500°N,43.0719°E;2270ma.s.l.;15Jun.2019;F.Vande Meutterleg.;FMT•8♂♂;43.0671°N,42.9471°E;2684ma.s.l.;15Jun.2019;J.H.Skevington leg.; CNC, CNC1386513, CNC1386514, CNC1386523, CNC1386528, CNC1386534, CNC1386537, CNC1386554,CNC1386558•1♂;42.9437°N,43.0539°E;2220ma.s.l.;15Jun.2019;X.Mengual leg.;ZFMK,ZFMK-DIP-00066506•2♂♂;42.9498°N,43.0718°E;2270ma.s.l.;15Jun.2019; X.Mengualleg.;ZFMK,ZFMK-DIP-00066505,ZFMK-DIP-00066508=ZFMK-TIS-8008813•5♂♂; Ushguli;42.56°N,43.04°E;2260ma.s.l.;15Jun.2019;J.vanSteenisleg.;JSB,2019-01.123,201901.124,2019-01.126to2019-01.128•2♂♂;42.9480°N,43.0700°E;2258ma.s.l.;15Jun.2019; S.Botleg.;SBA,SB.002950,SB.002951•1♂;Ushguli;42.94°N,43.05°E;2220ma.s.l.;15–17Jun. 2019;X.Mengualleg.;Malaisetrap;ZFMK,ZFMK-TIS-8010119•1♀;samedataasforpreceding; Fig. 74. Cheilosia (Cheilosia) uviformis Becker, 1894. Collected in Georgia. A.♂(SBA,SB.002945); habitus, lateral view; body length 7.9 mm. B.♂(SBA,SB.002944);head,lateralview;eyewidth 1.3 mm. C.♂(SBA,SB.002946);habitus,dorsalview;bodylength8.2mm.D.♀(SBA,SB.002943); head, lateral view; eye width 1.1 mm. Not to scale. European Journal of Taxonomy 1023: 1–181 (2025) 146 ZFMK,ZFMK-TIS-8010118•4♀♀;Ushguli;42.94°N,43.05°E;2220ma.s.l.;15–17Jun.2019;J.van Steenisleg.;JSB,2019-01.100to2019-01.103•3♂♂;42.9090°N,43.0070°E;2294ma.s.l.;16Jun. 2019;S.Botleg.;SBA,SB.002947toSB.002949•1♂;Ushguli;42.56°N,43.04°E;2260ma.s.l.; 16Jun.2019;J.vanSteenisleg.;2019-01.180;JSB•4♂♂,2♀♀;2kmSWofUshguli;43.0052°N, 42,8986°E;2550ma.s.l.;17Jun.2019;F.VandeMeutterleg.;FMT•1♀;2kmSWofUshguli; 43.0052°N,42,9036°E;2550ma.s.l.;17Jun.2019;F.VandeMeutterleg.;FMT•3♂;42.8980°N, 43.0080°E;2601ma.s.l.;18Jun.2019;S.Botleg.;SBA,SB.002944toSB.002946•1♀;samedata asforpreceding;SBA,SB.002943•3♂♂,6♀♀;2kmSWofUshguli;43.0052°N,42,8986°E; 2550ma.s.l.;18Jun.2019;F.VandeMeutterleg.;FMT•3♂♂;42.8964°N,43.0047°E;2658ma.s.l.; 18Jun.2019;J.H.Skevingtonleg.;CNC,CNC1386812,CNC1386814,CNC1386817•1♀;samedata asforpreceding;CNC,CNC1386806•1♂;ZagarariPass;42.91°N,43.09°E;2585ma.s.l.;18Jun. 2019; J. van Steenis leg.; JSB, 2019-01.145. Genetics DNA barcodes of European and Caucasian specimens of C. uviformis cluster together with high support (BS = 100%). Remarks ReportedfromtheCaucasusforthefirsttime. Biology Remarkably, only sampled in 2019 while areas of occurrence were also visited in other years. Collected between 14 June and 20 June at an altitude between 1800 and 2684 m a.s.l. All specimens were caught visiting willow Salix sp. catkins on alpine and subalpine grasslands. Distribution Europe and Caucasus (Georgia). Cheilosia (Cheilosia) vansteenisi sp. nov. urn:lsid:zoobank.org:act:C7EDACEF-AE70-4B0C-87FF-50B8AA0661E3 Figs 75–76 Differential diagnosis Cheilosia vansteenisi sp. nov. is morphologically and genetically very close to C. aerea. The easiest character to distinguish them is the pile on the posterodorsal corner of the anterior anepisternum: pilose in C. aerea, but bare in C. vansteenisi. Other differences are the darker legs in C. vansteenisi, which are black, except for the base and apex of protibia and mesotibia in the male which are dark brown (in C. aereatibiaeareextensivelyyellowatbaseandapex),scutumslightlyfinerpuncturedandterga shinier (tergum III almost entirely shiny in C. vansteenisi vs extensively pruinose medially in C. aerea). Moreover, male of C. vansteenisi sp. nov. has the face with denser pruinosity (Fig. 76A) and the frons with dense pruinosity; the female of C. vansteenisi, on the other hand, has the frons pruinose in anterior part (shiny in C. aerea), postpedicel black (Fig. 76B) (usually in C. aerea at least basoventral corner dark orange) and terga with only very few black pile in posteromedial parts of terga III–IV (in C. aerea with extensive black pile medially on terga II–IV). Our new species is similar to species of the proximagroup(Vujićet al. 2013), and within that group closest to C. proxima, but smaller (7–7.5 mm vs 7–9 mm) and with darker legs (Fig. 75A, C) (in C. proxima, tibiae usually distinctively yellow at base). The male has denser pruinosity on face (Fig. 76A), frons, postpronotum and terga with more and denser pruinosity, scutum medially with an area of short black pile at the level of wing bases (Fig. 75A) (short black pile on this area is missing in BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 147 C. proxima), terga and sterna on average with less black pile, sterna less densely pruinose with shiny spots on sterna I–II (sterna I–II entirely pruinose in C. proxima),surstyluswithfieldofmicrotrichia (Fig. 76D) (absent in C. proxima) and dorsal lobe of postgonite long and pointed with straight dorsal margin (Fig. 76C) (in C. proxima the lobe is shorter and less pointed and the dorsal margin has an extension). The female of C. vansteenisi sp. nov. has the frons extensively pruinose in anterior part (shiny in C. proxima), scutum with shorter and more adpressed pile, terga II–III shinier and tergum IV with yellow pile (medially with black pile in C. proxima). Etymology This new species is named after Jeroen van Steenis, our friend and the collector of the paratype. We name this species after him to acknowledge his immense contribution to the study of Syrphidae. Species epithet to be treated as a noun in the genitive case. Material examined Holotype GEORGIA•♂;Racha-LechkhumiandKvemoSvaneti,Tsana;42.9160°N,43.1428E;1975ma.s.l.; 19 Jun 2019; X. Mengual leg.; ZFMK, ZFMK-TIS-8008772 = ZFMK-DIP-00066391. Paratype GEORGIA – Samegrelo-Zemo Svaneti•1♀;Mestia;43.02°N,42.89°N;2600ma.s.l.;13Jun.2019; J. van Steenis leg.; JSB, 2019-01.121, ZFMK-TIS-8009610. Description Male Length. Body 7.5 mm, wing 7 mm. head. Face bare, with distinct facial tubercle, black, densely pruinose, below lunule narrower than an eye; parafacia black, pruinose, white pilose. Clypeus pruinose, about one and a half times as long as wide. Frontal triangle black, pruinose, long black pilose. Length of eye contiguity about 1.2 the length offrons.Angleofapproximationofeyesca90°.Verticaltriangleblack,shiny,ocellartriangleshiny, long black pilose and with few shorter yellow pile. Occiput pruinose, short yellow and long black pilose. Lunule dark yellow, with distinct medial arm, separating acetabula. Scape black, anteriorly with black and yellow setae; pedicel black, anteriorly with black setae; postpedicel blackish, pruinose, about as wide as high; arista black, with short pile, pile much shorter than diameter of arista at base. Eye with dense, yellow pile. thorax. Scutum black, shiny, except postpronotum densely pruinose and notopleural area slightly pruinose,finelypunctured,withlongyellowpile,intermixedwithsparseoftenlongerblackpile,black piledominantonlyinanterolateralcorners,posteriorlyinthecenterwithfieldofshorterectblackpile. Scutellum shiny, with long erect yellow pile and sparse erect black pile intermixed, and long black setae along posterior margin. Pleura black, slightly pruinose; anterior anepisternum bare; pile on pleura white except in posterodorsal corner of posterior anepisternum with few black pile and setae; katepisternum continuously pilose. Haltere yellow. Wing. Wing including alula entirely microtrichose, hyaline, veins dark brown. Legs. Coxae and trochanters black. Femora, tibiae and tarsi black except base and apex of protibia and mesotibia dark brown; profemur with mixed black and yellow pile; mesofemur with yellow pile; metafemur with anterodorsal and anteroventral long yellow pile, ventrally with short black setae; tibiae and tarsi with black and yellow pile. European Journal of Taxonomy 1023: 1–181 (2025) 148 abdomen. Tergum I pruinose, tergum II pruinose except lateral and posterior margins, tergum III pruinose anteriorly, pruinosity decreasing, from the anterior margin of tergum III towards the middle of the tergum, tergum IV shiny except narrow strip medially along anterior margin; terga with long erect yellow pile, pile shorter in center of terga II–III, except sparse short black pile intermixed in center of posterior half of tergum II and center of tergum III. Sterna I–IV pruinose except center of sterna I–II with shiny spot; sterna with long erect yellow pile, except along posterior margin of sternum II and in center of sterna III–IV where pile adpressed. Genitalia with surstylus 1.3 times as long as wide, and with largefieldofmicrotrichiaonlamella(Fig.76D);dorsallobeofpostgonitelongandpointed(Fig.76C). Female Length. Body 7 mm, wing 7 mm. Similar to the male, except for normal sexual dimorphism and the following characters. Posteroventral corner of face and genae with orange spot. Frons with mixed yellow and black pile. Frons shiny except anteriorly where pruinose. Occiput pruinose except shiny behind dorsal eye corner. Occiput yellow pilose. Scutum with semi-adpressed yellow pile, in center of posterior part mixed with black pile. Fig. 75. Cheilosia (Cheilosia) vansteenisi sp. nov. A–B.Holotype,♂(ZFMK,ZFMK-DIP-00066391); habitus, lateral and dorsal views; body length 7.5 mm. C–D.Paratype,♀(JSB,2019-01.121,ZFMKTIS-8009610); habitus, lateral and dorsal views; body length 7.0 mm. Not to scale. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 149 Scutellum with short yellow pile. Pile on pleura yellow. Legs black. Femora with yellow pile. Terga shiny except tergum I and the center of anterior margin of tergum II. Terga with yellow pile, except tergum II posteriorly in center with small area of black pile and tergum III medially with large triangular area of black pile. Sterna I–IV pruinose. Genetics Both DNA barcodes from the holotype and paratype cluster together with high support (BS = 100%). Remarks We consider the species rare, with only two specimens collected during three expeditions in three different years in the same area. Fig. 76. Cheilosia (Cheilosia) vansteenisi sp. nov. A, C–D.Holotype,♂(ZFMK,ZFMK-DIP-00066391); eye width 1.2 mm. A. Head, lateral view. B.Paratype,♀(JSB,2019-01.121,ZFMK-TIS-8009610);head, lateral view; eye width 1.2 mm. C. Postgonite, lateral view. D. Surstylus, lateral view. Scale bars: A–B not to scale; C–D in µm. European Journal of Taxonomy 1023: 1–181 (2025) 150 Biology Collected in mountains between 1975–2600 m a.s.l. Distribution So far only known from the type series localities in the Greater Caucasus in Georgia. Cheilosia (Cheilosia) variabilis (Panzer, 1798) Fig. 77 Syrphus variabilis Panzer, 1798: 10. Cheilosia variabilis – Stackelberg & Richter 1968: 249. — Stackelberg 1970: 59. — Barkalov 1993: 714. — Gujabidze 2002: 245. — Mengual et al. 2020: 21 (part). — Żóralski & Bystrowski 2021: 26. Differential diagnosis The combination of eye and face with pile and black legs of Cheilosia variabilis distinguish this species from all other Cheilosia of the region, except for C. borjomi sp. nov., C. melanopa and C. redi. It is similar to C. melanopa and C. redi but on average larger (9–12 mm vs 8–10 mm), with slenderer abdomen, legs all black (base and sometimes apex of tibiae yellow in those of C. melanopa and C. redi), in the male, the ventral part of the metafemur has black setae (with short black pile in C. melanopa and C. redi) and in the female, the metatibia has black pile anterolaterally (yellow in that of C. redi) and scutum with shorter semi-adpressed yellow and black pile and with sparse, longer, more erect black pile (with short erect yellow pile in that of C. melanopa). It is very similar to C. borjomi; see Differential diagnosis of that species for differences. Despite small genetic differences with European populations of C. variabilis, no consistent morphological differences were found. The male genitalia of C. variabilis arefiguredinFrancuskiet al. (2009). Material examined Collected in 2018, 2019, 2021 and 2023; see Mengual et al. (2020) for detailed records from 2018. Genetics DNA barcodes of C. variabilis are grouped in one cluster without high support (BS < 90%), comprising a group of sequences from European specimens (BS < 90%) and another group of sequences with the Caucasian individuals (BS = 95.4%). Remarks Some records of C. variabilis in Mengual et al. 2020 actually are C. borjomi sp. nov., and are reported as such in the account of C. borjomi. Biology During our expeditions, collected between 30 April and 26 June at an altitude between 751 and 2300 m a.s.l. Often found near forest or shrubs or near tall vegetation in meadows. Males sit on leaves oftreesandbothsexesvisitavarietyofflowers,oftenwhiteumbellifers. Distribution WesternandCentralPalaearctic,intowesternSiberia.DistributionwithintheCaucasusdifficulttoassess because previous records could also be Cheilosia borjomi sp. nov., but reported from Armenia, Georgia and Russia. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 151 Cheilosia (Cheilosia) velutina Loew, 1840 Fig. 78 Chilosia velutina Loew, 1840: 33. Chilosia velutina – Stackelberg & Richter 1968: 249. — Stackelberg 1970: 64. — Peck 1988: 119. — Barkalov 1993: 724. — Mengual et al. 2020: 22. Cheilosia velutina Loew, 1848 [sic] – Gujabidze 2002: 245. Fig. 77. Cheilosia (Cheilosia) variabilis (Panzer, 1798). Collected in Georgia. A.♂(ZFMK,ZFMKTIS-8006822); habitus, lateral view; body length 10.0 mm. B.♂(ZFMK,ZFMK-TIS-8006822);head, lateral view; eye width 1.4 mm. C.♂(ZFMK,ZFMK-TIS-8006822);habitus,dorsalview;bodylength 10.0 mm. D.♀(SBA,SB.002954);head,lateralview;eyewidth1.4mm.Nottoscale. European Journal of Taxonomy 1023: 1–181 (2025) 152 Differential diagnosis Cheilosia velutina is a member of a group of closely related species, called the proximagroup(Vujić et al. 2013) in which the pilose eyes, posterior margin of scutellum with setae, usually partly yellow legs, continuously pilose katepisternum, pruinose sterna and the shape of postgonite are distinctive characters. For a full diagnosis of the Cheilosia proximagroupandforfiguresofthemalegenitaliaofC. velutina, seeVujićet al. (2013). Within the proxima group C. velutinaisbestidentifiedbythepoorlydeveloped facialtubercle,resultinginthefacebeingalmostflatbetweenfacialtubercleandpostclypeus(Fig.78B, D) (in the other species, facial tubercle well-developed, face in lateral view obviously concave between facial tubercle and postclypeus). Moreover, no other species in the proxima group have the combination of the postpedicel usually orange at least basoventrally and scutum coarsely punctured like in C. velutina. Material examined Species not collected. Genetics DNA barcodes of European specimens of C. velutina cluster together with high support (BS = 100%). Fig. 78. Cheilosia (Cheilosia) velutina Loew, 1840. A.♂(SBA);habitus,lateralview;collectedin Mongolia; body length 8.9 mm. B–C.♂(SBA,SB.004486);collectedintheNetherlands.B. Head, lateral view; eye width 1.3 mm. C. Habitus, dorsal view; body length 8.6 mm. D.♀(GPA);head,lateral view; collected in Germany; eye width 1.3 mm. Not to scale. BOT S. et al., Review of the genus Cheilosia (Diptera) from the Caucasus 153 Distribution Palaearctic. Within the Caucasus reported from Azerbaijan and Russia. Cheilosia (Cheilosia) vernalis (Fallén, 1817) Fig. 79 Eristalis vernalis Fallén, 1817: 55. Cheilosia vernalis – Stackelberg & Richter 1968: 250. — Peck 1988: 120. — Barkalov 1993: 721. — Gujabidze 2002: 245. — Barkalov & Mutin 2018: 484. — Mengual et al. 2020: 22. — Żóralski 2022: 68. Differential diagnosis Cheilosia vernalis is a small (body size: 5–8 mm) and variable species (Ståhls et al. 2008). In the Caucasus, mainly to be confused with C. confusa sp. nov., see the Differential diagnosis of that species to distinguish the two taxa. Also, see Prokhorov et al. (2020) for a key to distinguish C. vernalis from similar species. Cheilosia vernalis is similar to C. cynocephala, but on average smaller (body size 5–8 mm vs 7–9 mm), body with brown or black shine (with blue shine in C. cynocephala), wing hyaline (female C. cynocephala usually with faint blackish median spot), pile on scutum often predominantly yellow (black in C. cynocephala) and with the two basal tarsomeres of mesoleg often dark orange (black in C. cynocephala). In our tree (Supp.file1: Fig. S1), there are two specimens genetically in between C. vernalis and C. confusa which we call ‘Cheilosia sp.’ (ZFMK-TIS-8009292 and ZFMKTIS-8014649). They are morphologically very close to C. vernalis, but slightly different. Our sample sizeandthedifferencesaretoosmalltodrawfirmconclusionsontheidentityofthesetwospecimens. They could belong to the variation within C. vernalis or represent a new species; thus, we decided to leavethemunidentified. Material examined Collected in 2018, 2019, 2022 and 2023; see Mengual et al. (2020) for detailed records from 2018. Genetics DNA barcodes of C. vernalis cluster together without high support (BS < 90%) with the DNA sequences of C. confusa sp. nov., C. gemmula sp. nov., C. melanura, C. bracusi, C. triamilia, and two specimens left as Cheilosia sp. Biology During our expeditions, collected between 6 May and 2 August at an altitude between 1250 and 2885ma.s.l.,bothonlowflowersandonwillowSalix sp. catkins. Distribution Palaearctic. Within the Caucasus, known from Georgia and Russia. Cheilosia (Cheilosia) vulpina (Meigen, 1822) Fig. 80 Syrphus vulpinus Meigen, 1822: 29. Chilosia conops Becker, 1894: 385. Syn. by Claussen & Speight (1998). Chilosia conops – Stackelberg & Richter 1968: 245. — Stackelberg 1970: 59. — Peck 1988: 100.