Nephrotoma geniculata Yang & Yang, 1987

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 : 254-255

Nephrotoma geniculata Yang & Yang, 1987 ( Figs 26–33 )

Nephrotoma geniculata Yang & Yang, 1987: 131 (original description); Yang et al., 2006: 445 (redescription).

Redescription. Hypopygium with tergite ninth and sternite ninth fused totally ( Fig. 26 ). Tergite ninth with posterior margin straight, terminating into a pair of rounded lobes in lateral corners; tergite ninth having paired posterior extensions divided by a deep narrow notch; each posterior extension possessing a horn-shaped process which acute apically, curved inward, with several denticles on base; posterior margin of posterior extension truncated and toothed, teeth densely covered on dorsal and ventral surface; a black ridge arising from mediodorsal region of posterior extension, which equipped with several denticles on base ( Figs 27–29 ). Outer gonostylus lanceolate, apical half sharply narrowed ( Figs 26, 29 ). Inner gonostylus broad at base, terminating into a sharp black beak, dorsal crest narrow, extending from mesal region to terminal of beak ( Fig. 30 ). Sternite ninth almost entirely split in lateral surface, dorsal part truncated at apex, posterior margin of sternite ninth deeply concaved medially ( Figs 26, 29 ). Sternite eighth possessing an elongate triangular lobe, tongue-like, obtuse apically, directed ventrad ( Fig. 26 ). Aedeagal guide broad basally, gradually narrowed to tip, gonapophyses narrowed and elongated, rod-shaped ( Fig. 29 ). Semen pump with ejaculatory apodeme produced into two lobes, each enlarged apically, medially with a strongly raised ridge ( Fig. 31 ). Posterior immovable apodeme very short, acute apically ( Figs 32–33 ). Anterior immovable apodeme obtuse and widened ( Figs 32–33 ). Aedeagus very long, more than 21 times longer than semen pump, slightly broad at basal region, extended to third abdominal segment, and then returned to ninth abdominal segment ( Fig. 26 ).

Material examined. 1♂, China, Heilongjiang, Baoquanling , 7.V.2019, leg. Yixin Huang.

Distribution. China (Ningxia, Inner Mongolia, Heilongjiang, Hubei, Sichuan).

Remarks. The species is similar to N. retenta Alexander, 1935 from China, but separated by the presence of median lobe on sternite eighth (without any process in N. retenta ), and the posterior extension of tergite ninth divided by a deep narrow notch (divided by a U-shaped notch in N. retenta ).

Figures

Figures 26–33. Nephrotoma geniculate Yang & Yang, 1987. 26. Hypopygium, lateral view. 27. Tergite ninth, dorsal view. 28. Posterior extensions of tergite ninth, ventral view. 29. Hypopygium, ventral view. 30. Inner gonostylus, lateral view. 31. Ejaculatory apodeme, dorsal view. 32. Semen pump, lateral view. 33. Semen pump, dorsal view. Scale bars=0.2mm.