Strongylophthalmyia corniculata, Zhou & Evenhuis & Yang, 2023

Zhou, Jiale, Evenhuis, Neal L. & Yang, Ding, 2023, A review of the Strongylophthalmyia coarctata subgroup (Diptera, Brachycera, Strongylophthalmyiidae) from China, with the descriptions of three new species, ZooKeys 1168, pp. 329-353 : 329

Strongylophthalmyia corniculata sp. nov.

Figs 3 , 4-8 , 9-12

Type material.

Holotype (♂): China, Yunnan, Honghe, Lvchun, Huanglianshan, 2018.v.19, by Malaise trap (CAU).

Diagnosis.

Generally shiny black (Fig. 3 ); anterior half of frons yellowish brown (Fig. 4 ); antennal first flagellomere of male yellowish brown, ovate, with a short conical process (Figs 5 , 6 ); wing hyaline (Fig. 8 ); mid and hind femora yellow, with narrow dark brown ring subapically (Fig. 3 ); hind femur of male lacking inner basal process; distiphallus less than half as long as phallapodeme, lacking apical “glans” (Fig. 12 ).

Description.

Body length 2.2 mm, wing length 2.2 mm.

Male. Generally shiny black (Fig. 3 ). Face, parafacial and anterior half of frons yellowish brown (Figs 4 , 5 ). Antenna yellowish brown with arista dark brown (Fig. 5 ). Proboscis and palpus brown. Wing hyaline (Fig. 8 ); wing veins brown to dark brown. Halter white with base slightly darkened. Legs yellow with mid and hind femora narrowly dark brown subapically (Fig. 3 ); tarsomeres 4 and 5 dark brown.

Head (Figs 4 , 5 ) with frons finely inflated; parafacial with dense silvery tomentose stripe; gena with silvery tomentose stripe along eye margin; postgena bulging. Head chaetotaxy: 1 inner vertical seta, 1 outer vertical seta, 3 fronto-orbital setae, 1 ocellar seta, 1 postocellar seta. Clypeus band-like; palpus elongate, with long sparse golden setulae. Antennal scape with scattered marginal setae and 1 dominant dorsal seta; pedicel with single strong seta dorsally; first flagellomere (Figs 5 , 6 ) ovate, wider than long, densely covered with long white setulae, with a short conical process dorsally; antennal process (Fig. 6 ) with short dense white setulae, 0.7 × as long as first flagellomere, sharp at apex; arista longer than antennal process.

Thorax with mesonotum (Fig. 7 ) densely covered with short scattered golden setulae, in dorsal view with distinct transverse suture. Anepisternum with short setulae along notopleural suture. Scutellum (Fig. 7 ) subtriangular, broad, slightly inflated. Thoracic chaetotaxy: 1 postpronotal seta, 1 anepisternal seta, 2 notopleural setae, 1 dorsocentral seta, 1 posterior supra-alar seta, 1 scutellar seta. Wing (Fig. 8 ) with R4+5 and M1+2 almost parallel apically; apical section of M1+2 finely arched; M4 and CuA+CuP not reaching but very closely approaching wing margin; r-m located near basal one-third (0.36) of cell dm; apical section of M4 nearly as long as dm-m; alula small; anal lobe slightly narrowed. Legs with dense whitish yellow setulae; hind femur lacking inner basal process.

Abdomen covered with long dense setae. Tergite 1 weakly sclerotized. Pregenital sclerites relatively weakly sclerotized.

Male genitalia: Epandrium (Figs 9 , 10 ) short and broad, with long dense setae. Surstylus (Figs 9 , 10 ) with short stout setae on inner distal surface. Cerci (Figs 9 , 10 ) narrow, elongate, finger-like, with short dense setae. Hypandrium (Figs 11 , 12 ) broadly rounded anteriorly, strongly arched medially, with one pair of bifid, long anterior lobes. Phallapodeme (Figs 11 , 12 ) long, rod-like. Pregonite (Fig. 11 ) long, narrow, band-like, basally fused to inner surface of hypandrium. Phallic plate (Fig. 12 ) thickened, divided into two articulating sclerites. Distiphallus (Fig. 12 ) extremely short, less than half as long as phallapodeme, lacking apical “glans”, membrane microtrichose. Ejaculatory apodeme (Fig. 12 ) small, slightly curved.

Female unknown.

Etymology.

The specific epithet is derived from Latin corniculata, referring to the short conical antennal process of this new species.

Distribution.

China - Yunnan: Lvchun (Fig. 56 ).

Comparative notes.

This new species is similar to S. gibbifera Shatalkin, 1993 from Vietnam in that both have an ovate first flagellomere with a small, short antennal process, and a fully hyaline wing. The new species differs from S. gibbifera in the following characters: anterior half of frons yellowish brown (frons entirely black in S. gibbifera ); first flagellomere yellowish brown (yellowish brown with dorsal half dark brown in S. gibbifera ); antennal process conical, with sharp apex (short and blunt in S. gibbifera ); mid and hind femora narrowly dark brown subapically, hind tibia largely darkened (femora yellow with hind femur weakly darkened at apex, hind tibia darkened in middle in S. gibbifera ).

Figures

Figure 3. Strongylophthalmyia corniculata sp. nov., male, holotype, habitus, lateral view. Scale bar: 1 mm.

Figure 56. Known distribution of species of the Strongylophthalmyia coarctata subgroup in China and South Korea.

Figures 4 - 8. Strongylophthalmyia corniculata sp. nov., male, holotype: 4 head, dorsal view 5 same, lateral view 6 left antenna, lateral view 7 thorax, dorsal view 8 wing. Scale bars: 0.25 mm.

Figures 9 - 12. Strongylophthalmyia corniculata sp. nov., male genitalia: 9 external genitalia, posterior view 10 same, lateral view 11 internal genitalia, ventral view 12 same, lateral view. Abbreviations: cerc = cercus; dph = distiphallus; ea = ejaculatory apodeme; ep = epandrium; hyp = hypandrium; pgt = pregonite; phap = phallapodeme; pp = phallic plate; sur = surstylus. Scale bar: 0.1 mm.