Neurigona convexa, Lin & Wang & Yang, 2024

Lin, Chen, Wang, Mengqing & Yang, Ding, 2024, The genus Neurigona Rondani, 1856 (Diptera, Dolichopodidae) from Yunnan, China, with descriptions of seven new species and a key to the species of China, ZooKeys 1190, pp. 319-345 : 319

Neurigona convexa sp. nov.

Figs 4 , 8

Type material.

Holotype: ♂, China: Yunnan, Lvchun, Yakou, Shuikuxiafang, (23°3'25.2"N, 102°46'37.71"E), 1780 m, collected by Malaise trap, 2019.IV.19-V.19, Liang Wang and Xin Li (CAU). Paratypes: 3 ♂♂, the same data as holotype (CAU).

Diagnosis.

First flagellomere somewhat triangular. Wing subapically convex at anterior margin. Fore tarsomere 4 ventrally weakly swollen at extreme base and then weakly concave for a short distance. Ventral surstylus distinctly widened subapically, apically nearly finger-like; dorsal surstylus nearly as long as ventral surstylus, rather wide, apically somewhat narrow.

Description.

Male (Fig. 4A ). Body length 5.1-5.9 mm, wing length 5.0-5.7 mm.

Head metallic green with pale gray pollinosity; eyes very narrowly separated on middle portion of face. Hairs and bristles on head black, but postocular bristles and postero-ventral hairs pale yellow. Antenna (Fig. 8D ) pale yellow, pedicel yellow; first flagellomere dark brown, nearly triangular, almost as long as wide; arista subapical, dark brown, with short brown pubescence. Proboscis yellow with pale hairs; palpus yellow, but brown basally, with blackish setulae and two blackish setae.

Thorax yellow with fine pale yellow pollinosity; mesonotum dark brownish yellow, but brown on flat mid-posterior portion; scutellum dark brownish yellow; postnotum dark brown at basal margin; laterotergite with a small black stripe at anterior margin. Pteropleuron with a very small black subtriangular spot just below wing base. Hairs and bristles on thorax black, six strong dc, 10-11 irregularly paired acr, short, hair-like; scutellum with two pairs of bristles, lateral pair long and strong, median pair short and hair-like. Propleuron with one brown bristle on lower portion.

Legs mainly yellow, but mid and hind tibiae and tarsi brown to dark brown. Hairs and bristles on legs mostly black except hairs on fore coxa pale yellow. Fore coxa with five brownish bristles on antero-apical portion; mid coxa with three brownish anterior and apical bristles; hind coxa with one strong black outer bristle at basal 1/3. Fore tibia with one short ad. Mid tibia with three ad, two pd, and two black strong apical bristles. Hind tibia with three ad, three pd, three short apical bristles, and one row of brownish yellow comb-like bristles. Fore tarsus with very short hairs. Fore tarsomere 4 ventrally weakly swollen at extreme base and weakly incised outward, and with short and nearly erect ventral hairs; tarsomere 5 ventrally with short and nearly erect ventral hairs. Mid tarsomere 1 with two short ad, three short av, and four short thick apical bristles; tarsomeres 2-4 with several short spine-like ventral bristles. Hind tarsomere 1 with thick ventral bristles and three short thick apical bristles. Relative lengths of tibiae and five tarsomeres of legs LI - 7.1: 5.9: 2.2: 1.4:1.1: 0.9; LII 8.1: 8.2: 2.2: 1.3: 0.9: 0.8; LIII 11.2: 3.8: 3.6: 1.5: 1.2: 0.7.

Wing (Fig. 4B ) subapically convex forward at anterior margin; nearly hyaline, tinged brown; veins brown; R2+3 and R4+5 convex forward at apical 1/3 and somewhat parallel; M1+2 gently bent apically and convergent with R4+5; CuAx ratio 0.75. Squama brown with pale yellow hairs. Halter dark yellow with brown knob.

Abdomen yellow with pale yellow pollen; terga 2-5 each with large dark brown spot at middle; hypopygium shiny dark brown. Abdominal sternite 5 distinctly projected, large subtriangular (Fig. 9B ). Hairs and bristles on abdomen blackish except those on venter more or less yellow.

Male genitalia (Fig. 4C ): epandrium wider than long, with two lateral processes (one long finger-like; the other long and somewhat thick, apically slightly dilated with very short and acute apico-dorsal process). Ventral surstylus distinctly widened subapically, apically nearly finger-like; dorsal surstylus nearly as long as ventral surstylus, rather wide, apically somewhat narrow. Cercus somewhat round, white, bearing short pale yellow hairs. Hypandrium short and acute. Phallus somewhat short and thin, hidden with hypandrium.

Female. Unknown.

Distribution.

China (Yunnan).

Etymology.

The specific name refers to the wing subapically convex at anterior margin.

Remarks.

The new species is peculiar and can be easily separated from other known species of the genus by the wing subapically convex at anterior margin and arista shorter than head width.

Figures

Figure 4. Neurigona convexa sp. nov. A male habitus, lateral view B wing C genitalia, lateral view. Scale bars: 1 mm (A); 0.05 mm (B); 0.1 mm (C).

Figure 8. Antennae A Neurigona apicilata sp. nov. B Neurigona basicurva sp. nov. C Neurigona brevidigitata sp. nov. D Neurigona convexa sp. nov. E Neurigona huanglianshana sp. nov. F Neurigona quadrimaculata sp. nov. G Neurigona ventriprocessa sp. nov. Scale bars: 0.1 mm.

Figure 9. Abdominal sternite 5 (male) A Neurigona basicurva sp. nov. B Neurigona convexa sp. nov. C Neurigona huanglianshana sp. nov. D Neurigona ventriprocessa sp. nov.