Strongylophthalmyia flagellicornis, 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 flagellicornis sp. nov.

Figs 13-14 , 15-19 , 20-23

Type material.

Holotype (♂): China, Yunnan, Xishuangbanna, Mengla, Yaoqu, 840 m, 2020.xi.22, leg. Liang Wang (CAU). Paratypes: Same collection data as for holotype (9♂, CAU); China, Yunnan, Honghe, Gejiu, Lvshuihe, 505 m, 2019.iii.30, leg. Xin Li & Liang Wang (5♂1♀, CAU); China, Yunnan, Honghe, Lvchun, Huanglianshan, 1300 m, 2018.vi.16, leg. Liang Wang (2♂, CAU).

Diagnosis.

Generally shiny black (Figs 13 , 14 ); frons yellow (Fig. 15 ); antennal first flagellomere of male yellow, subrhombic, with a long slender process covered with dense black setulae (Figs 16 , 17 ); wing infumate, with large dark suffusion at apex (Fig. 19 ); mid and hind femora yellow with narrow dark brown ring subapically (indistinct on mid femur) (Figs 13 , 14 ); hind femur of male with one thorn-like inner basal process; distiphallus nearly as long as phallapodeme, with small apical “glans” (Figs 22 , 23 ).

Description.

Body length 4.2-4.7 mm, wing length 2.4-3.0 mm.

Male. Generally shiny black (Fig. 13 ). Frons, face, parafacial, and gena yellow (Figs 15 , 16 ). Antenna yellow; antennal process and arista blackish brown (Figs 16 , 17 ). Clypeus yellow to yellowish brown; proboscis brown; palpus yellow. Wing infumate, with large dark suffusion at apex (Fig. 19 ); wing veins brown to dark brown. Halter white with base slightly darkened. Legs yellow; mid and hind femora with narrow dark brown ring subapically (indistinct on mid femur) (Fig. 13 ); mid and hind tarsomeres 4 and 5 dark brown. Abdominal syntergite 1+2 with large median yellow patch in posterior half.

Head (Figs 15 , 16 ) with frons with minute shallow striations; parafacial with dense silvery tomentose stripe; gena with silvery tomentose stripe along eye margin; postgena bulging, with several white long setulae. 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 short dense golden setulae. Antennal scape with scattered marginal setae and 1 dominant dorsal seta; pedicel with single strong seta dorsally; first flagellomere (Figs 16 , 17 ) subrhombic, wider than long, densely covered with whitish yellow setulae, with a long slender process dorsally; antennal process (Fig. 17 ) with dense erect black setulae, 4.8 × as long as first flagellomere; arista shorter than antennal process.

Thorax with mesonotum (Fig. 18 ) densely covered with short scattered golden setulae, in dorsal view with distinct transverse suture. Anepisternum with short dense golden setulae posteriorly. Scutellum (Fig. 18 ) subtriangular, broad, slightly inflated. Thoracic chaetotaxy: 1 anepisternal seta, 2 notopleural setae, 2 dorsocentral setae, 2 posterior supra-alar setae, 1 scutellar seta. Wing (Fig. 19 ) with R4+5 and M1+2 slightly convergent apically; apical section of M1+2 clearly arched; M4 and CuA+CuP not reaching but very closely approaching wing margin; r-m located at basal two-fifth (0.4) of cell dm; apical section of M4 shorter than dm-m; alula small; anal lobe well developed. Legs with dense dark setulae; hind femur with one thorn-like inner basal process.

Abdomen covered with short to long dense setae. Tergite 1 normally sclerotized. Pregenital sclerites weakly sclerotized.

Male genitalia: Epandrium (Figs 20 , 21 ) long and narrow, subovate in lateral view, with long dense setae. Surstylus (Figs 20 , 21 ) with short stout setae on inner distal surface. Cerci (Figs 20 , 21 ) narrow, elongate, finger-like, fused along length, with 1 long subapical seta and several short setae. Hypandrium (Figs 22 , 23 ) narrowly rounded anteriorly, arched medially, with one pair of bifid anterior lobes. Phallapodeme (Figs 22 , 23 ) long, straight, rod-like, nearly as long as distiphallus. Pregonite (Fig. 22 ) very long, narrow, band-like, basally fused to inner surface of hypandrium. Phallic plate (Fig. 23 ) divided into two articulating sclerites. Distiphallus (Figs 22 , 23 ) extremely long, nearly as long as phallapodeme, unsegmented, with sclerotized bands and apical “glans”, membrane microtrichose. Ejaculatory apodeme (Fig. 23 ) relatively long, straight, narrow.

Female. Antennal first flagellomere yellow with anterior margin darkened, ovate, lacking process (Fig. 14 ); clypeus thick, bulbous; hind femur lacking process; abdomen without yellow patch on syntergite 1+2. Other characters same as those of male.

Etymology.

The specific epithet is derived from Latin flagell - and - cornis, referring to the long, whip-like antennal process of this new species.

Distribution.

China - Yunnan: Gejiu, Lvchun, Mengla (Fig. 56 ).

Comparative notes.

This new species resembles S. shatalkini Iwasa & Evenhuis, 2014 from Papua New Guinea and S. stylocera Shatalkin, 1996 from Philippines by having the long and slender antennal process. The new species differs from S. shatalkini in the following characters: frons yellow (entirely black in S. shatalkini ); antennal first flagellomere of male subrhombic, with antennal process 4.8 × as long as first flagellomere (ovate, with antennal process 4 × as long as first flagellomere in S. shatalkini ); femora yellow with mid and hind femora narrowly dark brown subapically (femora uniformly dark brown in S. shatalkini ); wing with distinct large dark suffusion at apex, and R4+5 and M1+2 slightly convergent apically (wing with broad median transverse band and faint small apical suffusion, and R4+5 and M1+2 almost parallel in S. shatalkini ). The new species can be separated from S. stylocera in the following characters: frons yellow (entirely black in S. stylocera ); antennal process of male with dense dark setulae (with white setulae in S. stylocera ); wing with distinct large dark suffusion at apex (wing hyaline in S. stylocera ); abdomen with a large median yellow patch on syntergite 1+2 in male (uniformly black in S. stylocera ).

Figures

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

Figures 13, 14. Strongylophthalmyia flagellicornis sp. nov., lateral habitus, lateral view: 13 male, holotype 14 female, paratype. Scale bars: 1 mm.

Figures 15 - 19. Strongylophthalmyia flagellicornis sp. nov., male, holotype: 15 head, dorsal view 16 same, lateral view 17 left antenna, lateral view 18 thorax, dorsal view 19 wing. Scale bars: 0.25 mm.

Figures 20 - 23. Strongylophthalmyia flagellicornis sp. nov., male genitalia: 20 external genitalia, posterior view 21 same, lateral view 22 internal genitalia, ventral view 23 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.