Scelolabes verasilvae, Barros & Freitas-Silva & Ale-Rocha, 2023

Barros, Luana Machado, Freitas-Silva, Rafael Augusto Pinheiro de & Ale-Rocha, Rosaly, 2023, Revision of Neotropical Scelolabes Philippi (Diptera, Hybotidae, Ocydromiinae): two new species and a proposal of delimitation, European Journal of Taxonomy 890 (1), pp. 49-70 : 61-66

Scelolabes verasilvae sp. nov.

urn:lsid:zoobank.org:act:19C18F93-93BA-4708-8A0B-F6CD3C0FDDED

Figs 5–6 , 7A

Diagnosis

Scutum ( Fig. 5D ) yellow, except for a broad black stripe occupying dorsocentral and intra-alar regions, slightly narrower anteriorly. Pleura ( Fig. 5A ) yellow, except spot on upper margin of anepisternum pale brown. Mediotergite yellow, except spot on lateral margin brown. Hind femur ( Fig. 5E ) swollen at apex, hind tibia slightly arched and swollen at apex.

Etymology

The epithet ‘ verasilvae ’ is named in honor of dipterologist Vera Cristina Silva, who collected a number of the specimens studied in the manuscript.

Type material

Holotype CHILE • ♂ (good condition, terminalia dissected); “ CHILE. [Cautín:], R.[egion] IX, PN [National Parkl] Nahuelbuta , 37°48′10″S / 73°01′27″ W, 1327 m, 8–10.ii.2005, YPT [Yellow Pan Trap], Araucaria / Chusquea forest [sic. Araucania], UCR A Tol C05-004” [white label]. “HOLOTYPE, Scelolabes verasilvae Barros, Freitas-Silva & Ale-Rocha ” [red label]; CNC.

Paratypes CHILE • 1 ♀; same collection data as for holotype except “ 37º49′42′′S 73º00′39′′W, 1138 m, 8–9. ii.2005, meadow & along stream, UCR AToL C05-002”; CNC • 1 ♂; “ Conguillio NP, 1150 m, Araucaria / Nothofagus , 5.ii.1988, L. Masner ”; CNC • 1 ♂, 2 ♀♀; same collection data as for holotype except “ 4.ii.1988 ”; CNC • 2 ♂♂; “ 14 km E Malalcahuello , 1570 m, 3–31.xii.1982, A. Newton & M. Thayer ”; CNC • 1 ♂; “ Cautin Prov. , Volcan, Villarrica, 15-19.xii. 1982, 1250 m, A. Newton & M. Thayer ”; MNHN • 1 ♀; “ Valdivia , 30kmW La Union, Las Trancas, Nothofagus , 25.ii.1988, L. Masner ”; MNHN • 1 ♀; “Region IX, PN Nahuelbuta , 8.ii.2005, sweep Araucaria forest (CH-01), L. Masner ”; CNC • 1 ♂, 1 ♀; “Region IX, PN Conguillio , 3.9 km S north entrance 38°39′01″S 71°39′45″W, 1239 m, 20-24. ii.2006, YPT, Nothofagus / Chusquea for”; CNC • 6 ♂♂, 4 ♀♀; “ Parque Nacional Conguillío , Auracania, -38.648216, -71.669870, 21–22.I.2023, A. Gonçalves col.”; INPA .

Description

Male ( Fig. 5A, C–G )

MEASUREMENTS. Body length: 4.5 mm. Wing length: 3.5 mm.

HEAD. Frons brown, shining, dichoptic, narrow, about same width of anterior ocellus. Very close eyes on face. Face 1.2× length of frons. Antenna ( Fig. 5C ) pale brown; scape as long as pedicel; postpedicel lanceolate, about 1.2× length of scape and pedicel combined, with dense brown microtrichia; stylus about 2 × length of antenna. Proboscis pale brown and short; palpus ( Fig. 5C ) pale yellow, short, oval, covered with dense yellow pruinosity and 1 long and slender seta. Two pairs of slender proclinate ocellar setae, 1 anterior long and 1 posterior very short. Occiput black ( Fig. 5D ), covered with dense grey pruinosity; postocular setae elongated, scattered, upper setae stronger.

THORAX. Shining. Pronotum dark brown, except lateral margin yellow. Scutum ( Fig. 5D ) longer than wide, yellow, except for a broad black stripe occupying dorsocentral and intra-alar regions, not including postpronotal lobe, slightly narrower anteriorly; median acrostichal area and postalar callus pale brown. Pleura ( Fig. 5A ) yellow, except spot on upper margin of anepisternum pale brown, with slightly grey pruinosity. Scutellum ( Fig. 5D ) pale brown on base and yellow on apex, with slightly grey pruinosity; 1 thin short lateral scutellar pair of setae and 1 long, strong and black apical scutellar bristle of setae. Mediotergite yellow, except brown spot on lateral margin, with slightly grey pruinosity. Acrostichal setae with 4 rows, dorsocentral uniserial, short, slender and sparse on scutum; several short and slender setae (acrostichal and dorsocentral) on prescutelar region; notopleuron with slightly grey pruinosity, 1 long and strong notopleural bristle and several shorter, slender bristles; several postpronotal setae short and slender; 2 postalar setae, 1 anterior long and strong and 1 posterior short and slender.

WING ( Fig. 5G ). Membrane pale brown: pterostigma brown, elongate and narrow; dm cell shorter than basal cells, approximately 2.5× as long as wide; bm cell 1.3 × length of cua cell; CuA vein complete, reaching CuP vein. Halter whitish yellow, stem with some setulae.

LEGS. Long and slender ( Fig. 5A, E ). All coxae whitish yellow, except hind coxa slightly darker; femora whitish yellow, except dorsal surface of hind femur pale brown; tibiae pale brown, hind tibia darker; tarsi light brown. Coxae subequal in length. Hind femur slightly swollen near apex. Hind tibia ( Fig. 5E ) arched and slightly swollen at apex. Chaetotaxy: fore femur without outstanding setae; mid femur with 1 long and strong anterodorsal subapical seta, 1 long and slender ventral seta at basal ⅓, 1 long and slender anteroventral seta at mid-length and 1 long and slender anteroventral seta at ⅓ of apical; hind femur with 1 long and slender anterodorsal subapical seta, a row of long and strong anteroventral setae, both inserted on short tubercles. Fore tibia without outstanding setae; mid tibia with 1 long and stronger anterodorsal seta at mid-length, 1 anteroventral and 1 posteroventral long and strong apical setae. Tarsi without outstanding bristles.

ABDOMEN ( Fig. 5F ). Shining. All tergites brown, whitish and weakly sclerotized anteriorly. Sternite 1–3 weakly sclerotized, hyaline; sternites 4–8 pale brown, weakly sclerotized anteriorly. All tergites with long and slender setae on apical margin.

MALE TERMINALIA ( Fig. 6A–F ). Hypandrium ( Fig. 6A ) short, 2× as long as wide, sub-quadrangular, with a short projection with an apical tuft of long and slender setae on the right side ( Fig. 6A ). Epandrial lamellae covered with several short and slender setae. Left epandrial lamella ( Fig. 6C ) subtriangular, shorter than right, 1.5× as wide as long; right epandrial lamella ( Fig. 6D ) broad, sub-quadrangular, as wide as long; presence of a long and slender dorsobasal projection behind right cercus, inserted close to bridge that links right to left epandrial lamellae ( Fig. 6B ). Left surstylus ( Fig. 6E ) long, slightly sharpened, with 1 row of long, slender setae close together on dorsal surface, 1 row of long, slender and scattered setae on ventral surface, all setae inserted on tiny tubercles; right surstylus ( Fig. 6F ) shorter, about ⅔ of left, right lobe thin and sharpened, left lobe rounded with short and slender setae, dorsal surface with a row of long, slender and scattered setae, inserted on tiny tubercles, ventral surface bare. Cerci symmetrical, short, subtriangular, weakly sclerotized, covered with short and slender setae ( Fig. 6B ). Subepandrial sclerite ( Fig. 6B ) with basal margin truncate, distal margin with slight concavity in the middle. Hypoproct ( Fig. 6B ) sub-quadrangular, with a short triangular projection in left margin. Bacilliform sclerite asymmetrical with short and slender setae.

Female ( Fig. 5B )

Similar to male.

Variation

Some specimens of S. verasilvae sp. nov. have a completely yellow acrostichal region.

Remarks

Scelolabes verasilvae sp. nov. resembles S. amorimi sp. nov. in the slender legs and coloration of the scutum, but the species differ in the coloration of the pleura. In S. verasilvae . the pleuron is yellow with a brown spot on the upper margin of the anepisternum, while in S. amorimi . the pleuron is mostly yellow, except for the brown anepisternum, and the presence of a brown spot on the katepisternum, anepimeron and meron.

Distribution

This species is known from Chile ( Fig. 7A ).

Figures

Fig. 5. Scelolabes verasilvae sp. nov. A, C–G. Holotype, ♂ (CNC). B. Paratype, ♀ (CNC). A. Lateral habitus. B. Lateral habitus of female. C. Antenna in lateral view. D. Scutum in dorsal view. E. Hind legs. F. Abdomen in dorsal view. G. Wing. Fig. 5B provided by Bradley Sinclair.

Fig. 6. Scelolabes verasilvae sp. nov., male terminalia. A. Ventral view. B. Dorsal view. C. Left lateral view. D. Right lateral view. E–F. Surstyli in frontal view. E. Left. F. Right. Scale bars = 0.1 mm.

Fig. 7. Geographical records of Scelolabes Philippi, 1865. A. S. amorimi sp. nov. and S. verasilvae sp. nov. B. S. bivittatus Philippi, 1865.