A new cave-dwelling species of Trimma (Teleostei, Gobiidae) from the Red Sea, with notes on Red Sea endemism in Trimma spp.

77 A new cave-dwelling species of Trimma (Teleostei, Gobiidae) from the Red Sea, with notes on Red Sea endemism in Trimma spp. Viktor N. Peinemann1, Lucia Pombo-Ayora1,2 , Walter A. Rich1, Michael D. Fox1, Darren J. Coker1,3 1 Marine Science Program, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia 2 Department of Marine Science, The University of Texas at Austin, Marine Science Institute, 78373 Port Aransas, Texas, USA 3 KAUST Coral Restoration Initiative (KCRI), King Abdullah University of Science and Technology (KAUST), 23955 Thuwal, Saudi Arabia Corresponding author: Viktor N. Peinemann (viktor[email protected]) Copyright: © Viktor N. Peinemann et al. This is an open access article distributed under terms of the Creative Commons Attribution License (Attribution 4.0 International – CC BY 4.0). Research Article Abstract A new species of the gobiid genus Trimma is described from the Farasan Banks in the southeastern Red Sea. The new species is characterized by having a predorsal midline with 7–8 scales, the fifth pelvic-fin ray unbranched, cheek and opercle scaleless, all pectoral-fin rays unbranched, and a dorsal fin VI + I,7, without elongate spines. In life, the species is bright yellow throughout, with a distinctive yellow-green longitudinal band in the central third of the dorsal fins. The new species inhabits caves on exposed offshore reefs at depths between 15 and 30 m where it occurs in small groups of up to 10 individuals. The new species appears to be sister to T. winchi from the western Indian Ocean. We also present a multilocus phylogeny (COI, 16S, Ptr, S7I1), including all known Red Sea Trimma and 21 non-Red Sea species, and an expanded supermatrix tree with 93 species to place Red Sea endemism in broader context. This brings the total number of Trimma species known from the Red Sea to 10, with eight appearing to be endemic to the region. The high proportion of endemism in the genus is noteworthy, even for the Red Sea, which has one of the highest proportions of endemic reef fishes in the Indo-Pacific. Moreover, K2P distances in the two widespread species suggest they may also represent cryptic endemic species, but further analyses are needed. The new species is currently known only from the Farasan Banks region despite extensive sampling along the Saudi Arabian Red Sea coast. Key words: Biodiversity, biogeography, COI, cryptobenthic, Indian Ocean, phylogeny, taxonomy Introduction The gobiid genus Trimma Jordan & Seale, 1906 is one of the most speciose genera of coral reef-associated fishes in the Indo-Pacific, with over 110 valid described species. Commonly known as pygmygobies due to their small body size (typically <30 mm SL), members of this genus can be found on most Indo-Pacific coral reefs. Along with the similarly diverse and small-bodied Eviota Jenkins, 1903, they frequently represent one of the most abundant gobiids on hard substrates of coral reefs (Winterbottom 2019). Like Eviota, species of Academic editor: Tihomir Stefanov Received: 18 May 2025 Accepted: 22 August 2025 Published: 9 October 2025 ZooBank: https://zoobank. org/13A27F9A-2CD1-44B1-911CC08ABC79EFB0 Citation: Peinemann VN, PomboAyora L, Rich WA, Fox MD, Coker DJ (2025) A new cave-dwelling species of Trimma (Teleostei, Gobiidae) from the Red Sea, with notes on Red Sea endemism in Trimma spp. ZooKeys 1255: 77–93. https://doi.org/10.3897/ zookeys.1255.159341 ZooKeys 1255: 77–93 (2025) DOI: 10.3897/zookeys.1255.159341 78 ZooKeys 1255: 77–93 (2025), DOI: 10.3897/zookeys.1255.159341 Viktor N. Peinemann et al.: A new cave-dwelling Trimma from the Red Sea Trimma frequently show strong site fidelity and microhabitat specialization, likely contributing to their rapid diversification. New species are being discovered frequently, and molecular analyses suggest that many widespread species may represent complexes of multiple cryptic species with restricted geographic distributions (Winterbottom et al. 2020). The Red Sea harbors a distinctive assemblage of Trimma species, with most being endemic to the region (Bogorodsky and Randall 2019). Most of these species show strong associations with specific reef zones or microhabitats. Trimma flavicaudatum (Goren, 1982) and T. avidori (Goren, 1978) often represent the dominant cryptobenthic species on many Red Sea reefs, in some cases with dozens of individuals per square meter (Coker et al. 2018). However, their niche overlap is limited, with typically only one of the species dominating in each habitat. Some species, including T. barralli Winterbottom, 1995 and T. sheppardi Winterbottom, 1984, primarily inhabit depths of at least 30 m, while others, such as T. mendelssohni (Goren, 1978), are common in the upper 10 m of the reef. Associations with caves, which are common for Trimma species throughout the Indo-Pacific, are also present in the Red Sea. Both T. fishelsoni Goren, 1985 and T. nubarum Winterbottom, Bogorodsky & Alpermann, 2023 live in cave-associated groups. The former prefers small groups of low density, while the latter can be observed in dense schools of upwards of 30 individuals, hovering above the substrate near the entrances of caves (pers. obs. of first author). During biodiversity surveys of offshore reefs in the Farasan Banks region of the Saudi Arabian Red Sea, we discovered a distinctive, yellow-colored species of Trimma inhabiting cave systems at depths between 15–30 m. While often co-occurring with other cave-associated Trimma species, this taxon was typically restricted to areas slightly deeper inside the cave and more closely associated with the cave substrate. Herein we describe this new species based on morphological and molecular evidence and discuss its relationship to other members of the genus, particularly its apparent sister species T. winchi Winterbottom 1984 from the western Indian Ocean. Materials and methods Morphological measurements and meristic counts follow standard protocols established by Richard Winterbottom to ensure comparability with previous work (Winterbottom 2019; Winterbottom et al. 2023 and references cited therein). Likewise, the format of the diagnosis and description follows the sequence of characters in the key to the genus (Winterbottom 2019) and other recent species descriptions (Winterbottom et al. 2023). We documented cephalic sensory papillae following established row naming conventions (Winterbottom 2011; Winterbottom and Erdmann 2015). Character ranges are reported as minimum – holotype – maximum, followed by the mean and number of specimens in parentheses. Values of the holotype are presented in bold. Specimens were collected from cave habitats at depths of 15–30 m using clove oil anesthetic and hand nets. Live and fresh coloration was documented through photographs taken immediately after collection and during in situ observations. Ex-situ photographs were taken in an upright photo tank with a Nikon Z7 camera body, Nikon Z MC 105 mm f/2.8 macro lens, and a Godox MF12 Macro flash. To enhance visibility of key taxonomic features, particu- 79 ZooKeys 1255: 77–93 (2025), DOI: 10.3897/zookeys.1255.159341 Viktor N. Peinemann et al.: A new cave-dwelling Trimma from the Red Sea larly the cephalic sensory papillae, specimens were temporarily stained with cyanine blue 5R (acid blue 113). For molecular analyses, we extracted genomic DNA from tissue samples using the Qiagen DNeasy Blood & Tissue Kit. A region of the cytochrome c oxidase subunit I (COI) gene was amplified using the primer sets FishF2 and FishR2 (Ward et al. 2005) and GOBYL6468 and GOBYH7696 (Thacker 2003). Resulting sequences were then cleaned and aligned in Geneious Prime 2025.0.3 to produce a 648-bp alignment. Pairwise genetic distances between species were calculated using MEGA11 using the Kimura 2-parameter (K2P) model (Kimura 1980; Tamura et al. 2021) on the COI alignment. We also amplified three additional loci from the same specimens: mitochondrial 16S rRNA using primers 16SarL and 16SbrH (Palumbi et al. 1991), nuclear S7 ribosomal protein intron 1 (S7I1) using primers S7I1F and S7I1R (Chow and Hazama 1998), and nuclear Protease III (Ptr) using primers PtrF2 and PtrR2 (Yamada et al. 2009). Ptr was included because it can help resolve deeper splits and has been used in the similarly speciose genus Eviota (Tornabene et al. 2013). The final concatenated alignment consisted of 648 bp COI, 588 bp Ptr, 904 bp S7I1, and 608 bp 16S. The multi-locus dataset comprised specimens from our studies and collections, including all described Red Sea Trimma, 21 nonRed Sea Trimma, and two likely undescribed taxa: one Red Sea species similar to T. anaima Winterbottom, 2000 and one Madagascar species similar to T. quadrimaculatum Hoese, Bogorodsky & Mal, 2015. These specimens are currently being worked on by the authors, but they were included here due to their relevance to Red Sea endemism in Trimma spp. A maximum-likelihood tree was inferred using W-IQ-TREE (Trifinopoulos et al. 2016) via the web interface at http://iqtree.cibiv.univie.ac.at/. Protein-coding genes (COI and Ptr) were partitioned by codon position; all loci were also partitioned by gene. The best-fit substitution model was automatically selected. Branch support was assessed with 1000 ultrafast bootstrap replicates. Sueviota aethon Peinemann, Pombo-Ayora & Tornabene, 2024 was included as an outgroup to root the tree. The phylogenetic tree was visualized using Interactive Tree Of Life (iTOL) v6 (Letunic and Bork 2024) and finalized in Adobe Illustrator 29.2.1. In addition to the multi-locus dataset, we constructed a supermatrix that combines the full concatenated data for our specimens (COI, Ptr, S7I1, 16S) with COI-only terminals for Trimma species not represented in our collection. We queried the Barcode of Life Data System (BOLD) for all such species, selecting one representative COI sequence per species, with preference for longer sequences and for records identified by recognized experts. These public COI sequences were aligned to the COI partition of our concatenated dataset; the remaining three loci for those added taxa were coded as missing data. This preserves the higher signal of our multi-locus sampling while placing it in the context of the majority of described species of Trimma. Supp. material 1 lists, for each added species, the species name as used in the tree, the BOLD Process ID and, where available, the corresponding GenBank accession number, the name of the specimen identifier, and the collection locality. Supp. material 2 lists information for specimens in our collection used for the multi-locus dataset and the COI and 16S GenBank accession numbers generated for this study. The final supermatrix tree included all 33 Trimma species from our multi-locus dataset plus 60 additional COI-only species from BOLD, for a total of 93 Trimma species. 80 ZooKeys 1255: 77–93 (2025), DOI: 10.3897/zookeys.1255.159341 Viktor N. Peinemann et al.: A new cave-dwelling Trimma from the Red Sea Type specimens have been catalogued and deposited in the ichthyology collection of the Royal Ontario Museum (ROM). All fieldwork was conducted under approval 20IAUCUC05 issued by the KAUST Institutional Animal Care and Use Committee (IACUC). Results Trimma berumeni sp. nov. https://zoobank.org/9759ABBF-2807-4C55-9925-7598731B789B Figs 1, 2 Mikey’s golden pygmygoby Type locality. Saudi Arabia, Red Sea: Farasan Banks, 18.5041°N, 40.6606°E. Type material. Holotype • ROM 116871, 13.6 mm SL male, Red Sea, Saudi Arabia, Farasan Banks, 18.5041°N, 40.6606°E, inside cave of exposed reef wall, 27 m depth, collected with clove oil and hand net, V. N. Peinemann, 5 June 2024. Paratypes • ROM 116872, n = 2, 13.3 mm SL male, Red Sea, Saudi Arabia, Farasan Banks, 18.5041°N, 40.6606°E, inside cave of exposed reef wall, 27 m and 15 m depth respectively, collected with holotype • ROM 116873, 13.8 mm SL male, Red Sea, Saudi Arabia, Farasan Banks, 18.8581°N, 40.3788°E, inside cave of exposed reef wall, 15 m depth, V. N. Peinemann, 6 June 2024 • ROM 116874, n = 3, 10.7 mm SL female, 10.9 mm SL male, and 10.7 mm SL male, Red Sea, Saudi Arabia, Farasan Banks, 19.8375°N, 39.9297°E, inside cave of exposed reef wall, 30 m depth, V. N. Peinemann, 19 May 2022. Diagnosis. A species of Trimma distinguished by the following combination of characters: predorsal midline with 7–8 scales; fifth pelvic-fin ray unbranched and 40–42% length of fourth ray; cheek and opercle scaleless; all pectoral-fin rays unbranched; body bright yellow throughout and without bars in life; dorsal fin VI + I,7; no elongate spines in dorsal fin; bony interorbital width 81–84% of pupil diameter; iris golden-yellow with melanophores except for golden ring around pupil and inverted golden triangle extending from ventral margin of pupil; fins translucent with yellow-green longitudinal band in central third of dorsal fins; a thin black midlateral line from above pectoral-fin base to caudal-fin base, visible in life and in preservative. Figure 1. Freshly collected Trimma berumeni sp. nov., holotype, ROM 116871. Photograph: V. N. Peinemann. 81 ZooKeys 1255: 77–93 (2025), DOI: 10.3897/zookeys.1255.159341 Viktor N. Peinemann et al.: A new cave-dwelling Trimma from the Red Sea Figure 2. Close-up of key features of Trimma berumeni sp. nov., preserved in ethanol, ROM 116871 (A, B, C, D, E, G), ROM 116874 (F). A. Lateral view of head showing cephalic sensory papillae, specimen stained with cyanine blue, papillae highlighted with black dots, papilla rows connected by dotted lines and labeled accordingly; B. Dorsal view of head, showing cephalic sensory papillae and nasal apparatus, specimen stained with cyanine blue, papillae highlighted with black dots, papilla rows connected by dotted lines and labeled accordingly; C. Ventral view of head, showing cephalic sensory papillae, gill opening, and pelvic-fin base; D. Caudal fin with sensory papillae; E. Male urogenital papilla; F. Female urogenital papilla, specimen stained with cyanine blue; G. Lateral view of whole fish (preserved in 75% ethanol). 82 ZooKeys 1255: 77–93 (2025), DOI: 10.3897/zookeys.1255.159341 Viktor N. Peinemann et al.: A new cave-dwelling Trimma from the Red Sea Description. Based on holotype and 6 paratypes 10.7–13.8 mm SL. Dorsal fin VI + I,7, second spine longest but not elongate extending to base of second dorsal-fin spine when adpressed; all rays of second dorsal fin branched; second dorsal fin not elongate, reaching posteriorly 23–26–30 (27%, 7) of caudal peduncle length; anal fin I, 8, all rays branched; anal fin not elongate, reaching posteriorly 23–30 (27%, 7) of caudal peduncle length; pectoral-fin rays 14–15, all unbranched; pectoral-fin reaching posteriorly to vertical above urogenital papilla; pelvic fin I, 5, fifth ray unbranched and 40–42 (41%, 7) length of fourth ray, which reaches posteriorly to between base of first and third anal-fin ray, pelvic rays 1 to 4 with one branching point each; basal membrane approximately 9–10% of fourth pelvic-fin ray; no fraenum; caudal fin with 2 dorsal and 2–3 ventral segmented unbranched rays, and 6 dorsal and 5 ventral segmented branched rays; caudal fin with four vertically aligned papillae at base and three rows of 9–10 papillae each extending from the vertically aligned papillae to posterior margin of caudal fin (Fig. 2D); male urogenital papilla elongated and narrow (Fig. 2E; female urogenital papilla short and bulbous (Fig. 2F). Lateral scales 24; anterior transverse scales 7–8, posterior transverse scales 7–8; cheek and opercle scaleless; 7–8 scales on predorsal midline; body scales ctenoid; circumpeduncular scales 12; scale rows in ventral midline between base of last anal-fin ray and first procurrent caudal-fin ray 7–8. Gill opening extending anteroventrally to between middle and posterior third of pupil (Fig. 2C); anterior naris tubular reaching anteriorly across upper lip to posterior margin of lower lip; posterior naris oval and pore-like with raised rim, separated from bony front of orbit by 1.6–2 times its diameter (Fig. 2B); bony interorbital width 81–84% of pupil diameter (82%, 7); no dermal ridge on midline of nape extending anteriorly from origin of first dorsal fin. Caudal peduncle depth as percentage of caudal peduncle length 30–41 (37.2%, 7); head length as percentage of SL 27–29–31 (29.3%, 7); horizontal eye diameter 40–45 (43.1%, 7); snout length 16–20 (18.9%, 7); and upper-jaw length 32–33 (32.6%, 7) as percentage of head length Number of papillae in each row (Fig. 2A): a = 6 (4); b = 1–2 (5); c = 5 (5); d = 3–4 (5); d’ = 3–4 (5); p = 6 (5); e-anterior = 7–9 (5); e-posterior = 7–9 (5); i-anterior = 6–7 (5); i-posterior = 7 (5); cs” = 3 (5); ot = 7–8 (4); oi = 3–4 (4); u = 4 (3); cp = 1 (5); n = 1 (5); f = 2–3 (5). Color pattern, live (Fig. 1). Body bright yellow throughout. Head primarily yellow with orange coloration around the jaws, snout, interorbital region and below the ventral margin of the eye. Individuals can activate five translucent whitish bars along dorsal margin of body, from above the pectoral fin base to the caudal peduncle, sometimes visible in situ. Head and body with numerous small melanophores scattered throughout, running along scale pockets in the dorsal third of body, and scattered without patterns below the midlateral line. Specimens smaller than 11 mm SL with few melanophores on ventral half of body. A thin black midlateral line running along body from above pectoral-fin base to caudal-fin base. Iris golden-yellow, peppered with melanophores, except in a golden ring surrounding the pupil and an inverted golden triangle extending from ventral margin of the pupil. Dorsal fins translucent with dense red, white, and black chromatophores along basal third, a yellow-green longitudinal band running along central third, and sparse red, white, and black chromatophores along distal third. Anal fin mostly translucent with red, white, and black 83 ZooKeys 1255: 77–93 (2025), DOI: 10.3897/zookeys.1255.159341 Viktor N. Peinemann et al.: A new cave-dwelling Trimma from the Red Sea chromatophores, without yellow-green pigmentation. Dorsal and ventral fifths of caudal fin translucent with scattered red and white chromatophores, central section of caudal fin yellow to yellow-green. Pectoral fins and pelvic fins hyaline. Color pattern, preserved (Fig. 2G). Head and body primarily light yellow in large and recently preserved specimens, slowly fading to white in small specimens older than a year. Melanophores remain scattered throughout. A thin black midlateral line just under scales, extending from above pectoral-fin base to caudal-fin base. Iris densely packed with melanophores, appearing mostly black. Dorsal and anal fins hyaline with melanophores scattered in the posterior third of each fin, growing denser towards the posterior margin of the fin. Pectoral, pelvic, and caudal fins hyaline. Etymology. Named in honor of Michael L. Berumen in recognition of his substantial contributions to our understanding of the ecology and biodiversity of Red Sea coral reefs. Mikey’s golden pygmygoby is suggested as the common name. Distribution and habitat. Trimma berumeni sp. nov. inhabits caves of exposed offshore reefs, where it moves along the surface of cave roofs and walls in small groups of three to ten individuals (occasionally it is also solitary). It is typically found deep within caves, rarely seen within the first 80 cm of a cave entrance. The habitat is similar to that of its sister species, Trimma winchi, in the Seychelles (Ryan Daly pers. comm.). Specimens were collected at depths between 15 and 30 m. While only two specimens were observed shallower than 20 m, the species is relatively common in caves at 30 m. Our collections and surveys were limited to 30 m, but it is likely that the species extends to greater depths. We observed this species exclusively on reefs with steep walls that extend well into the mesophotic. The species is present throughout much of the Farasan Banks in the southeastern Red Sea (Fig. 3). Despite extensive collections in similar habitats along 0500 1,000 km Trimma berumeni sp. nov. Trimma winchi R R e e d d S S e e a a A A r r a a b b i i a a n n S S e e a a I I n n d d i i a a n n O O c c e e a a n n A Figure 3. Map showing collection localities of Trimma berumeni sp. nov. (red diamonds; present study) and its sister species T. winchi (orange diamonds; Winterbottom 2019) in the Red Sea and Indian Ocean. 84 ZooKeys 1255: 77–93 (2025), DOI: 10.3897/zookeys.1255.159341 Viktor N. Peinemann et al.: A new cave-dwelling Trimma from the Red Sea the Saudi Arabian coastline north of the Farasan Banks, from Jeddah to Tiran, we have not observed this species anywhere but the Farasan Banks. It is possible that the species is endemic to the southern half of the Red Sea. Comparisons In the key to the genus (Winterbottom 2019), T. berumeni keys out to couplet 71 but does not match either of the two species in the couplet. Trimma berumeni differs from both in having 7 dorsal fin rays (vs 9 in Trimma imaii Suzuki & Senou, 2009 and 8 in Trimma matsunoi Suzuki Sakaue & Senou, 2012). It additionally differs from T. imaii in having a bony interorbital width wider than 80% of pupil width (vs 40% in T. imaii) and from T. matsunoi in having 7–8 predorsal midline scales (vs 6 in T. matsunoi). The general body, fin, and eye color is also clearly distinct in each species. In overall morphology, the T. berumeni is most similar to T. winchi, which is currently known from the Seychelles and the Chagos Archipelago (Fig. 4A). They share a uniform yellow body color, have a similar habitat, and a geographically close but non-overlapping distribution. The COI sequences of T. berumeni and T. winchi differ by a K2P distance of 6.4% (see Suppl. material 3 for K2P distances of Red Sea Trimma and sister taxa in Fig. 5B). Several traits can be used to separate the two species. These are summarized in Table 1. Notably, the two Chagos (type locality) male specimens of T. winchi have an elongate dorsal spine, which is absent in Ryan Daly’s photographs of T. winchi from the Seychelles. It has not been evaluated whether this represents a distinct species or intraspecific variation. In Table 1 we follow the original description in listing dorsal-spine elongation for T. winchi, but the variation warrants further investigation. Within the Red Sea, T. fishelsoni bears some similarity to T. berumeni. Both species have a primarily yellow body color, a yellow longitudinal band along the dorsal fins, and a primarily yellow caudal fin. Both species also have an Table 1. Comparison of key characters between Trimma berumeni sp. nov. and T. winchi. Data for T. winchi based on Winterbottom (1984), Winterbottom (2019), and examination of a photograph of holotype. Trimma berumeni sp. nov. Trimma winchi Geographic range Farasan Banks, southern Red Sea Seychelles and Chagos Archipelago Dorsal fin VI + I,7 VI + I,8 Elongate dorsal spines None; second spine longest reaching to base of second dorsal-fin spine when adpressed Second spine elongate, reaching posteriorly just beyond base of last dorsal-fin ray when adpressed (absent in Seychelles specimens) Second dorsal-fin length Last ray not elongate, reaching posteriorly 23–30% of caudal peduncle length Last ray elongate, reaching posteriorly two-thirds of caudal peduncle length Anal-fin length Last ray not elongate, reaching posteriorly 23–30% of caudal peduncle length Last ray elongate, reaching posteriorly two-thirds of caudal peduncle length Dorsal-fin color (alive) Black longitudinal basal stripe composed of large melanophores with scattered iridocytes; single yellow longitudinal band above it; distal third hyaline Black longitudinal basal stripe composed of large melanophores with scattered iridocytes; a central yellow longitudinal band, then a narrow hyaline band; distal quarter yellow Anal-fin color (alive) No yellow pigmentation, mostly translucent with red, white, and black chromatophores Mostly yellow, with basal band of melanophores and iridocytes Caudal-fin color (alive) Yellow with translucent dorsal and ventral margins Yellow throughout with distal margin of melanophores 85 ZooKeys 1255: 77–93 (2025), DOI: 10.3897/zookeys.1255.159341 Viktor N. Peinemann et al.: A new cave-dwelling Trimma from the Red Sea Figure 4. Comparison of species similar to Trimma berumeni sp. nov. in the Red Sea and Indian Ocean. A. T. winchi, holotype, ROM 41477, fresh, Salomon Atoll, Chagos Archipelago; B. T. fishelsoni, fresh, Straits of Tiran (northern Red Sea / Gulf of Aqaba), Saudi Arabia; C. T. fishelsoni, live, Obstruction Reef (Thuwal, central Red Sea), Saudi Arabia. Photographs: A. by R. Winterbottom; B, C. by V. N. Peinemann. overlapping distribution in the central to southern Red Sea and are associated with caves. Trimma berumeni can be distinguished from T. fishelsoni by having no elongate dorsal spines (vs second spine elongate and filamentous in 92 ZooKeys 1255: 77–93 (2025), DOI: 10.3897/zookeys.1255.159341 Viktor N. Peinemann et al.: A new cave-dwelling Trimma from the Red Sea Yamada T, Sugiyama T, Tamaki N, Kawakita A, Kato M (2009) Adaptive radiation of gobies in the interstitial habitats of gravel beaches accompanied by body elongation and excessive vertebral segmentation. BMC Evolutionary Biology 9(1): 145. https:// doi.org/10.1186/1471-2148-9-145 Supplementary material 1 COI-only taxa included in the expanded 93-species phylogenetic dataset Authors: Viktor N. Peinemann, Lucia Pombo-Ayora, Walter A. Rich, Michael D. Fox, Darren J. Coker Data type: xlsx Explanation note: For each species, the table lists the species name as used in the tree, the BOLD Process ID, and where available the corresponding GenBank accession number, the name of the specimen identifier, and the collection locality. Copyright notice: This dataset is made available under the Open Database License (http://opendatacommons.org/licenses/odbl/1.0/). The Open Database License (ODbL) is a license agreement intended to allow users to freely share, modify, and use this Dataset while maintaining this same freedom for others, provided that the original source and author(s) are credited. Link: https://doi.org/10.3897/zookeys.1255.159341.suppl1 Supplementary material 2 Specimens included in the multi-locus dataset generated for this study and used in the phylogenetic analyses, with associated voucher numbers, collection localities, and GenBank accession numbers for COI and 16S Authors: Viktor N. Peinemann, Lucia Pombo-Ayora, Walter A. Rich, Michael D. Fox, Darren J. Coker Data type: xlsx Copyright notice: This dataset is made available under the Open Database License (http://opendatacommons.org/licenses/odbl/1.0/). The Open Database License (ODbL) is a license agreement intended to allow users to freely share, modify, and use this Dataset while maintaining this same freedom for others, provided that the original source and author(s) are credited. Link: https://doi.org/10.3897/zookeys.1255.159341.suppl2 93 ZooKeys 1255: 77–93 (2025), DOI: 10.3897/zookeys.1255.159341 Viktor N. Peinemann et al.: A new cave-dwelling Trimma from the Red Sea Supplementary material 3 Pairwise genetic distances (Kimura 2-parameter) between COI sequences of Trimma species from the Red Sea and Indo-Pacific Authors: Viktor N. Peinemann, Lucia Pombo-Ayora, Walter A. Rich, Michael D. Fox, Darren J. Coker Data type: xlsx Explanation note: The new species, T. berumeni, is highlighted in bold. Values shown as percentages. GenBank accession numbers and collection localities are provided for each sequence. Cells are color-coded from yellow (high divergence) to green (low divergence) to aid visualization. Copyright notice: This dataset is made available under the Open Database License (http://opendatacommons.org/licenses/odbl/1.0/). The Open Database License (ODbL) is a license agreement intended to allow users to freely share, modify, and use this Dataset while maintaining this same freedom for others, provided that the original source and author(s) are credited. Link: https://doi.org/10.3897/zookeys.1255.159341.suppl3