Shadow and Glass: Black vein, hyaline intervein Geometridae of Central America

66 TROP. LEPID. RES., 35(2): 66-74, 2025 MATSON ET AL.: Black and hyaline geometrids Shadow and Glass: Black vein, hyaline intervein Geometridae of Central America Tanner A. Matson1, Winnie Hallwachs2 and Daniel H. Janzen2 1. Department of Entomology, National Museum of Natural History, Smithsonian Institution, Washington, DC 20560-0127, USA. 2. Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA. Corresponding Author: Tanner A. Matson, [email protected]. Date of issue online: 19 December 2025 Zoobank Registered: urn:lsid:zoobank.org:pub:425569B8-E633-496A-9160-6A8CD1DA6A61 Electronic copies (ISSN 2575-9256) in PDF format at: https://journals.flvc.org/troplep; https://zenodo.org; archived by the Institutional Repository at the University of Florida (IR@UF), http://ufdc.ufl.edu/ufir; DOI: 10.5281/zenodo.17860767 © The author(s). This is an open access article distributed under the Creative Commons license CC BY-NC 4.0 (https://creativecommons.org/ licenses/by-nc/4.0/). Abstract: Convergently phenotypic, black-veined geometrid moths of Central America (Mexico to Panama) with hyaline or partially hyaline intervein areas are reviewed. When flushed, all are mimics of day-flying clear-winged ithomiine nymphalid butterflies (Greta Hemming, Ithomia Hübner, etc.). Seven species of moths are treated, including three new species described from Costa Rica: Crocypus semihyalina Matson n. sp. (Larentiinae, Eudulini), Astyochia longirama Matson n. sp. (Ennominae, Ennomini), and Stibaractis dianawegeae Matson n. sp. (Ennominae, Ennomini). Erycinopsis perspicua (Butler) rev. stat. is reinstated from synonymy with E. diaphana Felder. Food plant data for Erycinopsis Felder and Stibaractis Warren are reported for the first time, and the distinctive larva of E. perspicua is illustrated for the first time. Key words: Área de Conservación Guanacaste (ACG); butterfly mimics; Costa Rica; DNA barcoding; Neotropical. INTRODUCTION Black-veined geometrid moths of Central America, characterized by hyaline to partially hyaline intervein areas, are part of a broader mimicry complex shared with various lepidopteran groups. These include papilionoids, particularly ithomiine nymphalids, as well as dioptine notodontids, pyraloids, and multiple noctuoid taxa (Beccaloni, 1997). The frequent misidentification of these moths, along with the realization that several geometrid species exhibiting this phenotype remained undescribed in Central America, served as the primary motivation for this study. Certain taxa with this phenotype, such as members of the genus Perigramma Guenée (e.g., P. vicina (Schaus)), are excluded from detailed treatment here, as their intervein areas are entirely white rather than hyaline. While this distinction minimizes confusion when specimens are photographed or pinned, it does not apply when these moths are alive and in flight, as they remain effective mimics. Crocypus perlucidaria macroleuca Prout (Ennominae) is also excluded from formal treatment, as its wings lack hyaline characteristics. However, the adult and male genitalia of this species are illustrated to aid in the diagnosis of a visually similar, newly described Crocypus Herrich-Schäffer species. The adult of Gonora hyelosiodes (Walker) is also illustrated but not formally treated, as its presence in Central America remains unconfirmed, a point elaborated in the Discussion. Although the prevailing approach in taxonomic descriptive papers is to focus on monophyletic groups, cases of phenotypic convergence, particularly within extensive mimicry complexes, may warrant an alternative strategy. Addressing nonmonophyletic but phenotypically similar groups of species may prove more practical in some instances for identification and the discovery of new species. MATERIALS AND METHODS Material holdings (including primary types) were examined from the following institutions: American Museum of Natural History (AMNH), New York City, New York, USA; Natural History Museum (NHMUK), London, United Kingdom; and National Museum of Natural History (USNM), Washington DC, USA. Genitalic preparations were made by the first author following the methods described in Lafontaine (2004). Preparations were stained with Chlorazol Black and slidemounted in Euparal. Images were taken using a Visionary Digital imaging system and images manipulated (background removed) with Adobe Photoshop (Adobe Systems, Mountain View, CA). Área de Conservación Guanacaste (ACG) specimen vouchers are given as ##-SRNP-######. A brief section titled ‘Molecular data’ in each species treatment summarizes statistics drawn from the ‘BIN Details’ page on the Barcode of Life Data Systems (BOLD) public data portal (BOLD, 2024). These statistics are based exclusively on cytochrome c oxidase I (COI) DNA barcodes that meet BOLD’s quality standards: a minimum length of 500 base pairs and fewer than 1% ambiguous bases (Ratnasingham & Hebert, 2013). BIN assignments are dynamic and may change as new sequence data are added. All genetic distances reported are calculated as uncorrected pairwise distances (p-distance). 67TROP. LEPID. RES., 35(2): 66-74, 2025MATSON ET AL.: Black and hyaline geometrids RESULTS LARENTIINAE: Eudulini Crocypus semihyalina Matson, new species (Figs. 1, 10) ZooBank registered: urn:lsid:zoobank.org:act:F45CCFB3-1B6B-465F-934112FBB1CD6077 Diagnosis: Male Crocypus exhibit filiform antennae, a characteristic that will often distinguish this genus from other visually similar Geometridae. Additionally, in males, the modified, upcurved, appressed, and tapering hind tarsus, coupled with a flap-like protuberance at the base of the inner margin of the hindwing appear to characterize the genus. Among congeneric taxa, the white subapical patch in C. semihyalina does not extend to the costa (Fig. 1), in contrast to the Central American C. perlucidaria macroleuca, where it does (Fig. 2). Additionally, the intervein areas of C. p. macroleuca are predominantly opaque, whereas in C. semihyalina these areas display pronounced semitransparency. In males (Fig. 10), the bilobed posterior process of the juxta, with each lobe bearing a tight cluster of spines, is much less extended than in C. p. macroleuca, in which the posterior process is extended on a large stalk (Fig. 11). Description: ADULT (Fig. 1). Head: Antenna black, filiform in male. Vertex orange; frons dorsally orange and ventrally black. Labial palpus mostly orange, but with some black scaling on outer surface, length about 1.5x diameter of eye. Thorax: Mostly gray, some orange scales near head; tegula gray. Legs mostly gray, hind tarsus strongly modified, appressed to abdomen, upcurved, tapering apically. Forewing: Forewing length, male: 23-24 mm. Forewing with broad grayish-black marginal areas, veins, and oblique shadowy, ill-defined medial band; areas between margins and veins semitransparent, somewhat whitish. Underside like upperside. Hindwing: Patterned like forewing, but without medial oblique band. Base of hindwing inner margin with small flaplike protuberance. Abdomen: Gray with lateral pairs of hair-brushes at anterior parts of A7 and A8 (similar to Graphidipus). Male genitalia: (Fig. 10) Similar to Graphidipus. Uncus tapering to acuminate apex. Arms of gnathos thick; gnathos with medial pair of spinate processes. Valve ear-shaped. Transitilla with medial bilobed swelling. Juxta with bilobed posterior process, each lobe bearing tight cluster of spines. Vesica with large patch of setaceous cornuti. Female genitalia: Unknown. LARVA. Unknown. Types: HOLOTYPE. ♂, COSTA RICA: Guanacaste, ACG, [Sector] Santa Maria, Mirador Santa Maria, (10.76631°, -85.30099°), el. 920 m, 24-X-2019, @ Light Trap, S. Rios, 19-SRNP-105197, USNMENT 01995316, [USNM]. PARATYPE. (1♂) ♂, same collection data as holotype, Genitalia slide: TAM-2024-539 (USNM 157133), 19-SRNP-105196, USNMENT 01995315, [USNM]. Etymology: The name semihyalina is derived from the Latin word “semi”, meaning “half,” and “hyalinus,” meaning “transparent” or “glass-like,” referring to the partially transparent intervein areas of this species’ wings. It is treated as a feminine adjective. Biology: Adults appear to be nocturnal, as both individuals in our type series were taken at light. The immature stages of this species are unknown. Distribution: Crocypus semihyalina is currently known only from its type locality in the montane forests of Cordillera Guanacaste, Costa Rica. Molecular Data: COI barcodes of C. semihyalina belong to a single BIN: BOLD:AEJ5782 (n = 2, Costa Rica). The distance to the nearest neighbor represented in BOLD, C. perlucidaria, is approximately 6.6%. Remarks: Only two species of Crocypus are currently known: the species described herein and C. perlucidaria, which comprises two subspecies. Both subspecies of Crocypus perlucidaria presently fall within the same BIN (BOLD:AAJ6163), which is why no distinction is made above in the Molecular Data section regarding the subspecies most closely related to C. semihyalina. The taxonomic status of these subspecies warrants further study. Although external phenotypic differences appear to correlate with geography, preliminary DNA barcode data indicate that a specimen from Honduras is more closely related to material from Brazil and Venezuela than to specimens from Costa Rica and Guatemala, which is perplexing. Pseudomennis dioptoides (Warren, 1905) (Fig. 3) Eudule dioptoides Warren, 1905: 341. Type locality: Costa Rica: San José. [NHMUK] Note: Warren described dioptoides from a male holotype. Locha hermes Druce, 1907: 309. Type locality: Colombia. [NHMUK] Note: Druce described hermes from a female holotype. Diagnosis: The intervein areas of Pseudomennis dioptoides are fully hyaline. The orange spot at the base of the forewing and the orange venter of the abdomen, found in both sexes, are diagnostic among visually similar species (Fig. 3). Additionally, the filiform antennae in both sexes help to distinguish this species. Biology: The period of adult activity is unknown and the immature stages of this species have not yet been described. Distribution: The range of Pseudomennis dioptoides is poorly defined. Historical records, which often lack precise geographic details, indicate a distribution from northwestern Costa Rica to Colombia. In Panama, records from Cerro Campana note an elevation of 3000 ft (~915 m). Molecular Data: No molecular data are available for this species. ENNOMINAE: Ennomini Astyochia longirama Matson, new species (Figs. 4, 12, 17) ZooBank registered: urn:lsid:zoobank.org:act:8C41C3E6-4B5C-4D83-8569856B95A3B2BD Diagnosis: In males, the hair-brush along the inner margin of the hindwing distinguishes A. longirama from all other black-veined, hyaline Central American geometrids, except for its congener, A. fessonia. The most notable morphological difference between these congeners is the length of the rami on the male bipectinate antennae; in A. longirama, the rami are nearly twice as long as those of A. fessonia. Additionally, the blackened veins of A. longirama (Fig. 4) are more diffuse compared to the more sharply defined veins of A. fessonia (Fig. 68 5). In the apical area of the forewing, A. longirama typically exhibits three whitish “cells” between the apical veins, whereas A. fessonia usually has one or two larger “cells,” with a very small third cell appearing only occasionally. The male genitalia of A. longirama (Fig. 12) feature a slender posterior process of the juxta that is relatively short, terminating well before the medial spinate process of the gnathos. In contrast, Costa Rican populations of A. fessonia (Fig. 13) have a posterior process of the juxta that extends to the medial spinate process of the gnathos. Figures 1-9. Adult, black-veined geometrid moths of Central America with hyaline or partially hyaline intervein areas. 1, Crocypus semihyalina, holotype, Costa Rica (ACG), 19-SRNP-105197 (USNMENT 01995316). 2, Crocpyus perlucidaria macroleuca, Costa Rica, USNM. 3, Pseudomennis dioptoides, Panama, USNM. 4, Astyochia longirama, holotype, Costa Rica (ACG), 11-SRNP-101861 (USNMENT 01950011). 5, Astyochia fessonia, Costa Rica, USNM. 6, Erycinopsis diaphana, Panama, USNM. 7, Erycinopsis perspicua, Costa Rica (ACG), 98-SRNP3754 (USNMENT 02051244). 8, Stibaractis dianawegeae, holotype, Costa Rica (ACG), 07-SRNP-101831 (USNMENT 01950038). 9, Gonora hyelosiodes, Peru (Cuzco), USNM. Scale bar = 2 cm. TROP. LEPID. RES., 35(2): 66-74, 2025 MATSON ET AL.: Black and hyaline geometrids 69 Figures 10-16. Male genitalia. A, genital capsule, B, phallus. 10, Crocypus semihyalina, paratype, TAM-2024-539 (USNM 157133). 11, Crocypus perlucidaria macroleuca, TAM-2024-540 (USNM 157134). 12, Astyochia longirama, paratype, TAM-2024-541 (USNM 157135). 13, Astyochia fessonia, TAM-2024-543 (USNM 157137). 14, Erycinopsis diaphana, TAM-2024-547 (USNM 157141). 15, Erycinopsis perspicua, TAM-2024-544 (USNM 157138). 16, Stibaractis dianawegeae, paratype, TAM-2024-391 (USNM 154298). Scale bar = 2 mm. TROP. LEPID. RES., 35(2): 66-74, 2025MATSON ET AL.: Black and hyaline geometrids 70 Description: ADULT (Fig. 4). Head: Antenna black; bipectinate in male, filiform in female. Vertex dark gray; frons mostly dark gray, with white posterolateral patches. Labial palpus skinny and gray; subequal to diameter of eye. Thorax: Patagium gray. Tegula with white dorsomedial scales and gray lateral scales. Mesothorax mostly white with gray middorsal stripe. Legs mostly dark gray with some white scales on inner surfaces. Forewing: Forewing length, male: 15-16 mm; female: 17 mm. Broadly blackened veins and wing margins, and whitish, semihyaline intervein areas. Upper postmedial area more broadly covered with black scales. Males with fovea present and base of anal vein raised on blister. Hindwing: Patterned like forewing. Males bearing white hair brush extending from basal fringe of inner margin. Fringe gray. Underside of both wings concolorous with upperside. Abdomen: Dorsum gray; lateral and ventral areas mostly white, but with dark gray lateral pinstripe. Tergites 3 and 4 of male with dense patches of scales. Male genitalia: (Fig. 12) Uncus slender and digitate. Gnathos well-developed; with medial spinate process. Valve simple. Juxta with posterior, medial knife-like process; process terminating well short of spinate gnathos (unlike A. fessonia). Aedeagus with tapered posterior extension; vesica with ca. 35 large spinose cornuti. Female genitalia: (Fig. 17) Papillae anales slender. Apophyses large, with free ends swollen; posterior apophysis nearly twice length of anterior apophysis. Ductus bursae short; colliculum well-developed. Corpus bursae with medial, signumlike pleated sclerites. LARVA. Unknown. Types: HOLOTYPE. ♂, COSTA RICA: Guanacaste, ACG, [Sector] Pitilla, Sendero Memo, (10.98518°, -85.42811°), el. 774 m, 02-IV-2011, @ Light Trap, R. Franco and F. Quesada, 11-SRNP-101861, USNMENT 01950011, [USNM]. PARATYPES. (5♂, 2♀) 1♂, COSTA RICA: Guanacaste, ACG, Pitilla, Pitilla, (10.98931°, -85.42581°), el. 675 m, 12-IV-2006, @ Light Trap, H. Cambronero and S. Rios, 06-SRNP-103076, USNMENT 01950004, [USNM] • 1♀, COSTA RICA: Guanacaste, ACG, Pitilla, Pitilla, (10.98931°, -85.42581°), el. 675 m, 04-IV-2011, @ Light Trap, R. Franco and F. Quesada, 11-SRNP102489, USNMENT 01950005, [USNM] • 1♂, COSTA RICA: Guanacaste, ACG, Pitilla, Pitilla, (10.98931°, -85.42581°), el. 675 m, 30-V-2008, @ Light Trap, H. Cambronero and F. Quesada, 08-SRNP-101668, USNMENT 01950006, [USNM] • 1♂, COSTA RICA: Guanacaste, ACG, Del Oro, Serrano (11.00023°, -85.45621°), el. 585 m, 31-V-2008, @ Light Trap, S. Rios and H. Cambronero, 08-SRNP-101772, USNMENT 01950007, [USNM] • 1♂, COSTA RICA: Guanacaste, ACG, Pitilla, Pitilla, (10.98931°, -85.42581°), el. 675 m, 17-V-2007, @ Light Trap, H. Cambronero and S. Rios, 07-SRNP-103495, USNMENT 01950008, [USNM] • 1♀, COSTA RICA: Guanacaste, ACG, Pitilla, Pitilla, (10.98931°, -85.42581°), el. 675 m, 03-IV-2011, @ Light Trap, F. Quesada and S. Rios, Genitalia slide: TAM-2024-542 (USNM 157136), 11SRNP-102263, USNMENT 01950009, [USNM] • 1♂, COSTA RICA: Guanacaste, ACG, Del Oro, Bosque Aguirre (11.00060°, -85.43800°), el. 620 m, 19-VI-2009, @ Light Trap, F. Quesada and S. Rios, Genitalia slide: TAM-2024541 (USNM 157135), 09-SRNP-105109, USNMENT 01950010, [USNM]. Etymology: The name longirama is derived from the Latin “longus,” meaning “long,” and “ramus,” meaning “branch,” referring to the notably long antennal rami of this species in comparison to its visually similar congener, A. fessonia. It is treated as a feminine adjective. Biology: Adults appear to be nocturnal, as the entirety of our type series were taken at light. The immature stages of this species are unknown. Distribution: Our records of A. longirama are all from ACG in northwestern Costa Rica, specifically within the mid-elevation (580-780 m) Isthmian-Atlantic rainforest on the Caribbean slope of the Cordillera Guanacaste. Molecular Data: Currently, COI barcodes of A. longirama belong to the BIN: BOLD:AAE0761 (n = 8, Costa Rica). The maximum pairwise distance within this BIN is approximately 0.15%, while the distance to the nearest neighbor is about 6%. No other predominantly black-veined Astyochia have been DNA barcoded so far as known. Astyochia fessonia Druce, 1885 (Figs. 5, 13) Astyochia fessonia Druce, 1885: 158. Type locality: Costa Rica: Irazú, 6000-7000 ft; Colombia: Bogotá. [NHMUK] Note: Druce described fessonia from a male and female syntype. Currently, only the syntype from Colombia is labeled as a type in the NHMUK collection, although both syntypes should be present. Parrhesia illineata Warren, 1897: 465. Type locality: [Colombia]: Bogotá. [NHMUK] Note: Warren described illineata from a male holotype. Diagnosis: Diagnostic differences with respect to A. longirama are discussed under that species. Genitalia: Male: (Fig. 13) Description based on Costa Rican populations: Uncus slender and digitate. Gnathos well-developed; with medial spinate process. Valve simple. Juxta with posterior, slender process; process terminating past medial process of gnathos (unlike A. longirama). Aedeagus with tapered posterior extension; vesica with ca. 20 large spinose cornuti. Female: No material available for study. Biology: The period of adult activity is unknown and the immature stages of this species have not yet been described. Distribution: Currently, A. fessonia is believed to range from Costa Rica to Bolivia. However, South American specimens in institutional collections have not been rigorously examined, and some may be misidentified, potentially representing A. nigrivenata Warren or other undescribed species. It is likely that further study will reveal a more restricted distribution for A. fessonia. Molecular Data: No molecular data are available for this species. Erycinopsis diaphana Felder, 1874 (Figs. 6, 14, 18) Erycinopsis diaphana Felder, 1874: pl. 105, fig. 9. Type locality: [Colombia]: Bogotá. [?NHMUK] Note: Felder illustrated diaphana based on a male specimen. Hyalocampa specularis Warren, 1900: 187. Type locality: Ecuador: Cachabí, low country. [NHMUK] Note: Warren described specularis from a syntype male and syntype female. However, only the syntype male was located and examined in the collections of the NHMUK. Diagnosis: The intervein areas of E. diaphana are fully hyaline, exhibiting a distinct opalescent sheen. In males of both E. diaphana and E. perspicua, the darkened margin of the fovea and the blackened scale patch between the blackened inner margin and the fovea are diagnostic features. However, the blackened scale patch appears absent in a putatively undescribed South American congener (see Remarks). The male genitalia are also distinctive within the genus, with the enlarged furca slightly angled to the left (in microscope view) (Fig. 14), in contrast to other visually similar species, such as TROP. LEPID. RES., 35(2): 66-74, 2025 MATSON ET AL.: Black and hyaline geometrids 71 Gonora, where it is directed to the right. Additionally, unlike most other black-veined hyaline geometrid moths, the black scales in Erycinopsis do not diffuse over the veins; instead, the veins are sharply outlined in black. Erycinopsis diaphana and E. perspicua both occur, in part, in Central America, but their geographic distributions differ. The known range of Erycinopsis perspicua extends from Nicaragua to central Costa Rica, while E. diaphana is found from Panama to the low-elevation rainforests of western Ecuador. A third, undescribed species appears to inhabit higher elevations of the Andes (see Remarks). One of the clearest differences between E. perspicua and E. diaphana lies in the hyaline patch in the subcostal area of the forewing. In E. perspicua, this patch is typically narrower and cloudier, whereas in E. diaphana it is completely transparent. Additionally, the hyaline areas in E. diaphana exhibit a distinct opalescent sheen, while any sheen in E. perspicua is faint or imperceptible. Preliminary male genitalic dissections reveal further differences. The furca in E. perspicua appears to meet but not extend beyond the medial process of the gnathos, whereas in E. diaphana the furca extends well beyond it. Moreover, the cornuti on the vesica of E. diaphana appear to be significantly larger than those in E. perspicua, based on limited dissections. Genitalia: Male: (Fig. 14) Uncus hood-like. Socii welldeveloped. Gnathos with broad, rugose medial projection. Valve broad, with strong costal sclerite. Furca large, thick, with dense comb-like patch of stiff setae; directed left (in microscope view). Furca extending well past medial projection of gnathos. Phallus with slender, extended posterior heel; vesica with patch of ca. 9-10 appressed cornuti (cornuti larger than E. perspicua). Female: (Fig. 18) Ductus bursae short and wide. Corpus bursae ovate, with slight posterior sclerotized patch; bearing denticulate tear-drop shaped signum. Biology: Like Erycinopsis perspicua (see below), adults of E. diaphana are most likely diurnal. The immature stages of this species are unknown. Distribution: The concept of E. diaphana may be overly broad; records span from the rainforests of Panama to the lowelevation rainforests of western Ecuador. Molecular Data: The corresponding BIN(s) for E. diaphana are currently uncertain. It is possible that BIN: BOLD:AEO8465 (n = 2, Ecuador) represents this species, but we are unable to confirm this. To better anchor the name E. diaphana, additional sampling from South America is essential. Figures 17-20. Female genitalia. 17, Astyochia longirama, paratype, TAM-2024-542 (USNM 157136). 18, Erycinopsis diaphana, TAM-2024548 (USNM 157142). 19, Erycinopsis perspicua, TAM-2024-545 (USNM 157139). 20, Stibaractis dianawegeae, paratype, TAM-2024-392 (USNM 154299). Scale bar = 2 mm. TROP. LEPID. RES., 35(2): 66-74, 2025MATSON ET AL.: Black and hyaline geometrids 72 Remarks: Mid-elevation Andean populations (1200-2150 m) historically referred to as Erycinopsis diaphana from Peru and Ecuador, tentatively associated with BIN: BOLD:ABV4737, display distinct male morphological differences. Notable traits include significantly shorter and thicker antennal rami, measuring roughly half to two-thirds the length seen in other populations of E. diaphana. Furthermore, males from these populations lack the blackened scale patch typically found between the blackened inner margin and the fovea; instead, this area is lightly suffused with gray scales. We consider this entity undescribed, as none of the type material for the three available names exhibit these morphological features. Erycinopsis perspicua (Butler, 1876), revised status (Figs. 7, 15, 19, 21) Locha perspicua Butler, 1876: 120. Type locality: Nicaragua: Chontales. [NHMUK] Note: Butler described perspicua from a male holotype. This specimen, housed at the NHMUK, has its body detached from the wings. The wings are mounted on cardstock, while the remaining parts of the body are preserved in an accompanying gelatin capsule. The genitalia of this specimen have not been dissected. Taxonomic Act: Erycinopsis perspicua was synonymized with E. diaphana by Druce (1885), which at the time was also treated as a synonym of Locha hyalina (Walker), a quite different species (Pitkin, 2002). Erycinopsis perspicua is here reinstated as a species based on examination of Costa Rican specimens and the Nicaraguan holotype, which differ from E. diaphana in both morphology (see Diagnosis under E. diaphana) and DNA barcode. These differences support the taxonomic reinstatement of E. perspicua. Diagnosis: Diagnostic differences are discussed under E. diaphana. Genitalia: Male: (Fig. 15) Uncus hood-like, with slight medial constriction. Socii well-developed. Gnathos with broad, rugose medial projection. Valve broad, with strong costal sclerite. Furca large, thick, with dense comb-like patch of stiff setae; directed left (in microscope view). Phallus with slender, extended posterior heel; vesica with small patch of appressed cornuti. Female: (Fig. 19) Ductus bursae short and wide. Corpus bursae ovate, with slight posterior sclerotized patch; bearing denticulate ovate signum. Larva: (Figs. 21A-D) Head yellow. Thorax predominantly yellow (except some dorsal banding on T3). A1-A5 banded black and white, with white bands in the middle of each segment and black between segments. Banding continued over A6-A8, but only dorsally; laterally and ventrally yellow, including prolegs. Pupa: (Fig. 21F) Predominantly yellow, with scattered black spots throughout. Large dorsal white patch with black spotting merging to create striped appearance. Biology: In ACG, larvae of E. perspicua are abundant; however, despite several decades of nocturnal UV light collecting, no adult specimens have been captured at night, suggesting that this species is diurnal. Online observations (e.g., iNaturalist) also record adults only during daylight hours. In ACG, E. perspicua has been reared 186 times from Turpinia occidentalis (Swartz) Don (Staphyleaceae) (Fig. 21), indicating that this species is a dietary specialist. The larva has been observed folding the Figure 21. Late instar larva, pupal shelter, and pupa of Erycinopsis perspicua. A, B, late instar larva, C, head, D, rear, specimen voucher: 09SRNP-2626 (USNMENT 01949188). E, pupal shelter, F, pupa, specimen voucher: 17-SRNP-1554. TROP. LEPID. RES., 35(2): 66-74, 2025 MATSON ET AL.: Black and hyaline geometrids 73 leaf blade to create a shelter for pupation (Fig. 21E). The pupa retains similar integumental coloration to the larva (Fig. 21F). Distribution: The range of E. perspicua is not well defined; our records extend from the rainforests of Nicaragua south to central Costa Rica. Molecular Data: COI barcodes of E. perspicua are currently assigned to BIN: BOLD:AAC6965 (n = 30, Costa Rica). The genetic distance to the nearest neighbor, Erycinopsis nr. diaphana (BIN: BOLD:AEO8465, Ecuador), is approximately 3.2%. Stibaractis dianawegeae Matson, new species (Figs. 8, 16, 20) ZooBank registered: urn:lsid:zoobank.org:act:CEF08390-B9B6-4D79-8E0C75E4192E96A7 Diagnosis: In its native range, Stibaractis dianawegeae is easily distinguished from other Central American geometrid moths. While Erycinopsis (Figs. 6, 7) and Pseudomennis dioptoides (Fig. 3) share a similar forewing pattern, the intervein areas in these species are fully hyaline, contrasting with the cloudy, almost entirely white intervein areas of S. dianawegeae, which are further characterized by suffused black scaling over the veins (Fig. 8). Additionally, these other taxa lack the distinctive longitudinal grayish-black and white stripes on the thorax and abdomen that are prominent in S. dianawegeae. Instead, they typically have solid black to grayish-black abdomens, with P. dioptoides exhibiting orange coloration on the venter and Erycinopsis having a pale white venter. Stibaractis dianawegeae can be distinguished from its only congener, S. dioptis (Felder & Rogenhofer), by both geography and morphology. Stibaractis dianawegeae occurs in Central America, whereas S. dioptis is known only from South America. Morphologically, S. dianawegeae is characterized by more extensively darkened and suffused wing veins, giving the species a distinctly dusky appearance. Differences in the male genitalia are also notable, particularly in the structure of the two terminal processes of the phallus (Fig. 16B, see also Pitkin, 2002: fig. 597). In S. dianawegeae, the shorter, shelf-like process is larger and more strongly serrate, while the longer terminal process, which bears two subprocesses, is morphologically distinct: the medial subprocess is blunt and thumb-like in S. dianawegeae but sharply pointed in S. dioptis; likewise, the terminal subprocess is apically indented in S. dianawegeae and pointed in S. dioptis. In females, the signum is larger and more prominent in S. dianawegeae. However, this diagnosis is based on limited dissections, and intraspecific variation has not yet been thoroughly assessed. Description: ADULT (Fig. 8). Head: Antenna bipectinate in male with long rami; ciliate and slightly serrate in female; scales above grayish black. Vertex grayish black. Frons grayish black except for white patches of scales dorsolaterally. Labial palpus upcurved, slightly larger than diameter of eye; mostly grayish black but with white scales basally. Haustellum well-developed. Thorax: Patagium mostly grayish black. Tegula and remainder of thorax with longitudinal grayish black and white stripes. Legs mostly grayish black but with some white scaling. Epiphysis well-developed. Tibial spur formula 0-24. Forewing: Forewing length, male: 22-24; female: 22-25 mm. White with blackened perimeter, suffused blackened scales over veins, and an oblique medial black band; areas between veins cloudy and semi-transparent. Fovea present. Hindwing: Patterned like forewing. Undersides of both wings concolorous with uppersides. Abdomen: Alternating white and black longitudinal stripes. Male genitalia: (Fig. 16) Uncus triangulate, apically hood-like. Gnathos with broad, papillated medial projection. Valve vertically broad but longitudinally short. Costobasal area of valve with short, dense patch of spine-like setae. Juxta ill-defined and weakly sclerotized. Phallus short and complex, strongly sclerotized terminally; with shorter, arcing, shelf-like process bearing marginal serration and ending in pointed apex, opposite longer process bearing digitate subprocesses, medial subprocess thumb-like, distal subprocess with apical dentation; vesica apparently with single spinose cornutus. Female genitalia: (Fig. 20) Posterior apophysis ca. half-length of anterior apophysis. Ostium bursae large and wide; lamella postvaginalis heavily sclerotized. Ductus bursae short and wide. Corpus bursae posteriorly sclerotized and irregular; small, inwardly depressed, disc-shaped non-spinate signum positioned anteriorly. LARVA. Unknown. Types: HOLOTYPE. ♂, COSTA RICA: Guanacaste, ACG, [Sector] Pitilla, Pitilla, (10.98931°, -85.42581°), el. 675 m, 17-III-2007, @ Light Trap, R. Franco and F. Quesada, 07-SRNP-101831, USNMENT 01950038, [USNM]. PARATYPES. (5♂, 5♀) 1♂, COSTA RICA: Guanacaste, ACG, Pitilla, Sendero Mismo, (10.98758°, -85.41967°), el. 680 m, On Celastrus vulcanicolus, 26-III-2011, ecl. 13-V-2011, Calixto Moraga, 11-SRNP-30839, USNMENT 01950019, [USNM] • 1♀, COSTA RICA: Guanacaste, ACG, Pitilla, Sendero Mismo, (10.98758°, -85.41967°), el. 680 m, On Celastrus vulcanicolus, 20-IV2011, ecl. 27-V-2011, Manuel Rios, 11-SRNP-31092, USNMENT 01950020, [USNM] • 1♀, COSTA RICA: Guanacaste, ACG, Pitilla, Sendero Mismo, (10.98758°, -85.41967°), el. 680 m, On Celastrus vulcanicolus, 26-IV-2011, ecl. 29-V-2011, Manuel Rios, 11-SRNP-31089, USNMENT 01950021, [USNM] • 1♀, COSTA RICA: Guanacaste, ACG, Pitilla, Pitilla, (10.98931°, -85.42581°), el. 675 m, 17-II-2007, @ Light Trap, S. Rios and F. Quesada, 07-SRNP-101045, USNMENT 01950024, [USNM] • 1♀, COSTA RICA: Guanacaste, ACG, Pitilla, Sendero Mismo, (10.98758°, -85.41967°), el. 680 m, On Celastrus vulcanicolus, 20-IV-2011, ecl. 10-V-2011, Manuel Rios, 11SRNP-31088, USNMENT 01950027, [USNM] • 1♂, COSTA RICA: Alajuela, ACG, Rincon R.F., Sendero Albergue Crater, (10.84886°, -85.32810°), el. 980 m, 12-III-2010, ecl. 22-III-2010, Carolina Cano, 10-SRNP-1408, USNMENT 01950030, [USNM] • 1♂, COSTA RICA: Guanacaste, ACG, Pitilla, Sendero Memo, (10.98518°, -85.42811°), el. 774 m, 02-X-2021, S. Rios and G. Pereira, 21-SRNP-100406, USNMENT 01980034, [USNM] • 1♀, COSTA RICA: Guanacaste, ACG, Pitilla, Sendero Evangelista, (10.98680°, -85.42083°), el. 660 m, 21-V-2004, ecl. 29-V-2004, Manuel Rios, Genitalia slide: TAM-2024392 (USNM 154299), 04-SRNP-32905, USNMENT 01950040, [USNM] • 1♂, COSTA RICA: Guanacaste, ACG, Pitilla, Sendero Mismo, (10.98758°, -85.41967°), el. 680 m, On Celastrus vulcanicolus, 26-V-2018, ecl. 13-VI-2018, Manuel Rios, 18-SRNP-30952, USNMENT 01950041, [USNM] • 1♂, COSTA RICA: Guanacaste, ACG, Pitilla, Sendero Mismo, (10.98758°, -85.41967°), el. 680 m, On Celastrus vulcanicolus, 26-V-2018, ecl. 19-VI-2018, Manuel Rios, Genitalia slide: TAM-2024-391 (USNM 154298), 18-SRNP-30937, USNMENT 01950042, [USNM]. Other material examined: 19♂, 8♀, all from ACG, Costa Rica. Etymology: The species epithet dianawegeae honors Diana Wege of New York City, USA, for her exceptional support of staff operations in Costa Rica’s Área de Conservación Guanacaste (https://www.acguanacaste.ac.cr/index.php). Biology: Stibaractis dianawegeae has been reared 24 times in ACG from Celastrus vulcanicola Donnell Smith (Celastraceae) (labeled as Celastrus volcanicolus on moth specimens). Unfortunately, no larval images were taken for these collections. However, the caterpillar is likely striking, with observation notes indicating it is black with yellow spots. Distribution: Stibaractis dianawegeae is currently known only from type material collected in the rainforests of northern Costa Rica, where it typically occurs at elevations ranging from 6501000 m (~2130-3280 ft). Molecular data: Thirty-nine specimens of S. dianawegeae (BOLD BIN: BOLD:AAC7310) have been DNA barcoded, revealing a pairwise distance of approximately 4.5% TROP. LEPID. RES., 35(2): 66-74, 2025MATSON ET AL.: Black and hyaline geometrids 74 from its nearest-neighbor, “Nephodia” sp. (BOLD BIN: BOLD:AFH6788). The maximum intraspecific pairwise distance is about 0.3%. To date, Stibaractis dioptis from South America does not appear to have been DNA barcoded. Remarks: The origin of the spinate processes of the phallus is difficult to determine—whether they arise from the aedeagus or the vesica remains uncertain. We tentatively interpret a single spinate cornutus as originating from the vesica, with the remaining processes arising from the terminal portion of the aedeagus. Pitkin (2002), however, did not classify any as cornuti. DISCUSSION Addressing non-monophyletic yet phenotypically similar groups provides a practical framework for resolving widespread misidentification and discovering new species. Although this study focuses exclusively on the more tractable Central American fauna, black-veined moths with hyaline or partially hyaline intervein areas exhibit greater diversity in South America. It is with near certainty that additional undescribed species remain hidden within this mimicry complex. Gonora hyelosiodes (Fig. 9) was excluded from this study, as its presence in Central America could not be confirmed. The only Central American records we could locate are the holotype of its junior synonym, Gonora aequatorialis (Boisduval, 1870), reported by Boisduval as originating from Honduras, and a second specimen he reports in the same description from Mexico. The holotype, housed in the NHMUK, matches other specimens of Gonora hyelosiodes from South America. Whether this species truly occurs in Central America or if its locality was erroneously reported remains unresolved. “Gonora” vitrina (Druce), although still listed in modern geometrid catalogues (Scoble, 1999; Rajaei et al., 2022), is a dioptine notodontid in the genus Phanoptis (Miller, 2009), into which it was originally described (Druce, 1885). As such, it is outside the scope of this study and has been excluded. This misplacement should be addressed in future geometrid catalogues. The publication of the first food plant records for Erycinopsis and Stibaractis are expected to facilitate the discovery of larval stages for congeners in South America, as the species treated in this study appear to be dietary specialists. The larva of Erycinopsis perspicua is particularly striking (Figs. 21A-D), and it is likely that the larva of Stibaractis dianawegeae, described in field notes as having a black body with yellow spots (though currently unphotographed), will be equally distinctive. The vivid coloration and patterning observed in both adults and larvae, along with their associated food plants, strongly suggest that these species are advertising pronounced chemical defenses or mimicking others with such defenses. ACKNOWLEDGMENTS TAM is grateful to the Smithsonian National Museum of Natural History and the Smithsonian Entomology Department for institutional and office support. We would like to acknowledge the generous financial support provided by the Guanacaste Dry Forest Conservation Fund (https://www. gdfcf.org) and the private donors and governments whose contributions help fund this organization. All yy-SRNP-nnnnn vouchered specimens were collected, exported, and DNA barcoded under Costa Rican government permits issued to BioAlfa (Janzen and Hallwachs, 2019) (R-054-2022-OT-CONAGEBIO; R-019-2019-CONAGEBIO; National Published Decree #41767), JICA-SAPI #0328497 (2014) and DHJ and WH (ACGPI-036-2013; R-SINAC-ACGPI-061-2021; Resolución Nº001-2004 SINAC; PI-028-2021). LITERATURE CITED Beccaloni, G. W. 1997. Ecology, natural history and behaviour of ithomiine butterflies and their mimics in Ecuador (Lepidoptera: Nymphalidae: Ithomiinae) Tropical Lepidoptera 8(2): 103-124. Boisduval, J. B. A. D. de 1870. Considérations sur des lépidoptères envoyés du Guatemala à M. de l’Orza. Rennes, Paris, Oberthür et fils. 101 pp. BOLD Systems. 2024. Barcode of Life Data Systems (Version 4). https://www. boldsystems.org. Last accessed 20 February 2025. Butler, A. G. 1876. On the Lepidoptera referred by Walker to the genus Dioptis of Hübner. Cistula Entomologica 2(15): 107-121. Druce, H. 1885. Insecta: Lepidoptera-Heterocera. In: Godman, F. D., Salvin, O. (Eds.), Biologia Centrali-Americana, Zoologia. Vol. 1. London, Taylor and Francis. i-xxxii + 1-490 pp., 40 pls. Druce, H. 1907. Descriptions of new species of Heterocera belonging to the families Syntomidae, Hypsidae, Cyllopodidae, Dioptidae, and Erateininae. Annals and Magazine of Natural History; Zoology, Botany, and Geology 19: 299-311. Felder, C. 1874. Lepidoptera Heterocera, pp. 75-107, pls. In: Felder, C., Felder, R., Rogengofer, A. F. (Eds.), Reise der österreichischen Fregatte Novara um die Erde, in den Jahren 1857, 1858, 1859, unter den Befehlen des Kommodore B. von Wüllerstorf-Urbair, Zoologischer Theil, Bd. 2(2). Wien, Kaiserlich-Königlichen Hof-und Staatsdruckerei. 140 pls. Lafontaine, J., 2004. The Moths of America North of Mexico (Fascicle 27.1.), Noctuoidea, Noctuidae (part): Noctuinae, Agrotini. Lawrence, Kansas, Allen Press. 385 pp. Miller, J. S. 2009. Generic revision of the Dioptinae (Lepidoptera: Noctuoidea: Notodontidae) Part 1: Dioptini. Bulletin of the American Museum of Natural History 321: 1-674. Pitkin, L. M. 2002. Neotropical ennomine moths: a review of the genera (Lepidoptera: Geometridae). Zoological Journal of the Linnean Society 135(2-3): 121-401. Rajaei, H., Hausmann, A., Scoble, M., Wanke, D., Plotkin, D., Brehm, G., Murillo-Ramos, L., Sihvonen, P. 2022. An online taxonomic facility of Geometridae (Lepidoptera), with an overview of global species richness and systematics. Integrative Systematics 5(2): 145-192. Ratnasingham, S., Hebert, P. D. 2013. A DNA-based registry for all animal species: the Barcode Index Number (BIN) system. PloS One 8: e66213. Scoble, M. J. 1999. The Geometrid Moths of the World: A Catalogue (Lepidoptera, Geometridae). Collingwood, Victoria, CSIRO Publishing. 1016 pp. Warren, W. 1897. New genera and species of Thyrididae, Epiplemidae, and Geometridae, from South and Central America and the West Indies, in the Tring Museum. Novitates Zoologicae 4: 408-513. Warren, W. 1900. New genera and species of American Drepanulidae, Thyrididae, Epiplemidae, and Geometridae. Novitates Zoologicae 7: 117225. Warren, W. 1905. New American Thyrididae, Uraniidae, and Geometridae. Novitates Zoologicae 12: 307-379. TROP. LEPID. RES., 35(2): 66-74, 2025 MATSON ET AL.: Black and hyaline geometrids