Nephrotoma nigrostylata Alexander, 1935

Men, Qiulei, Yu, Dong & Sun, Mengwei, 2023, Description of a new species in the genus Nephrotoma (Diptera: Tipuloidea: Tipulidae) from China, with redescriptions of hypopygiums of six species, Zoological Systematics 48 (3), pp. 249-263 : 257-262

Nephrotoma nigrostylata Alexander, 1935 ( Figs 53–60 )

Nephrotoma nigrostylata Alexander, 1935b: 204 (original description); Yang et al., 2006: 446 (redescription).

Redescription. Hypopygium with tergite ninth and sternite ninth fused at basal two thirds ( Fig. 53 ). Tergite ninth medially concaved in a shallowly V-shaped notch, producing into two flattened black lobes on posterior margin; ventral surface of lobes toothed, tooth extending to media region of posterior margin ( Figs 54–55 ). Outer gonostylus slender, widened basally, narrowed to tip, acute and curved apically, its ventral margin equipped with three or four denticles ( Figs 53, 55–56 ). Inner gonostylus strongly curved dorsally in C-shaped, apical half enlarged, truncated apically, dorsal edge with a conical process (con pr) and an elongated lobe (el lb), posterolateral part appearing as a black obtuse lobe ( Figs 55–57 ). Sternite eighth having an elongated triangular lobe, tongue-shaped in caudal view, directed ventral ( Figs 53, 55 ). Sternite ninth more massive than tergite ninth, split laterally, deeply concaved on posterior margin ( Figs 53, 55 ). Aedeagal guide acute at tip, gonapophyses enlarged at apex, its inner margin straight, outer margin denticulate ( Fig. 55 ). Semen pump with ejaculatory apodeme divided by a deeply V-shaped notch into two lobes, each lobe obtuse apically, with a raised ridge medially ( Fig. 58 ). Posterior immovable apodeme slightly S-shaped, widened at base, almost same length to ejaculatory apodeme ( Figs 59–60 ). Anterior immovable apodeme massive and obtuse apically in lateral view ( Figs 59–60 ). Aedeagus restricted in eighth and ninth abdominal segments, more than seven times longer than semen pump, almost same thickness throughout except filiform apical region ( Fig. 53 ).

Material examined. 1♂, China, Anhui, Huangshan, Fangcun , 29.V.2020, leg. Qiulei Men.

Distribution. China (Anhui, Zhejiang, Hubei, Fujian, Chongqing, Sichuan, Guangxi, Guizhou).

Remarks. The species shares the presence of tonglike lobe on sternite eighth with N. parvirostra Alexander, 1924 , widely distributed in the Eastpalaearctic Region including China. It distinctly differs from the latter species by the tergite ninth with two black flattened lobes on lateral corners (without such lobe in N. parvirostra ), the outer gonostylus with three or four denticles on ventral margin (without such denticle in N. parvirostra ), and the inner gonostylus without dorsal crest (with distinctly serrated dorsal crest in N. parvirostra ).

Figures

Figures 53–60. Nephrotoma nigrostylata Alexander, 1935. 53. Hypopygium, lateral view. 54. Tergite ninth, dorsal view. 55. Hypopygium, ventral view. 56. Outer gonostylus and inner gonostylus, lateral view. 57. Inner gonostylus, inner view. 58. Ejaculatory apodeme, dorsal view. 59. Semen pump, lateral view. 60. Semen pump, dorsal view. Scale bars=0.2mm.