Nephrotoma didyma Yang & Yang, 1987

Yang, Qi-Cheng, Liu, Qi-Fei, Pan, Zhao-Hui, Liu, Xiao-Yan & Yang, Ding, 2020, Nephrotoma Meigen (Diptera, Tipulidae) from Xizang Autonomous Region, China, ZooKeys 973, pp. 123-151 : 123

Nephrotoma didyma Yang & Yang, 1987 Figs 17-19 , 20-25

Nephrotoma didyma Yang & Yang, 1987: 131. Type localty: China: Xizang, Mainling Co.

Diagnosis.

Pronotum yellow with a brownish spot on lateral side. Mediotergite yellow with dark-brown posterior margin (Figs 17 , 19 ). Posterior margin of tergite 9 with a jaw-shaped protuberance; spade-shaped protuberance with two short horns at posterior margin (Fig. 22 ). Posterior margin of sternite 8 with meniscus-shaped protrusion (Figs 20 , 23 ).

Material examined.

4 males (CAU), China: Xizang, Yigong, 2017.VI.7, 2236 m, Qicheng Yang (light trap). 3 males (CAU), China: Xizang, Yigong, 2017.V 6, 2274 m, Qicheng Yang (light trap). 6 males (CAU), China: Xizang, 106K, 2017.V.17, 2289 m, Qicheng Yang (light trap).

Description.

Male (n = 13): body length 9.5-12.0 mm, wing length 10.0-12.0 mm, antenna length 3.0-4.0 mm.

Head (Figs 17 , 19 ). Mainly yellow. Vertex with brown spot near inner margin of eye. Occipital marking dark brown, bell-shaped, extended to top of vertex. Frontal tubercle relatively high. Dorsal part of rostrum including nasus brownish black. Hairs on head dark brown. Antenna dark brown except scape yellow and pedicel dark yellow; first flagellomere 1.4 times longer than second one. Proboscis yellow, with brown hairs. Palpus brownish grey, with brown hairs.

Thorax (Figs 17 , 19 ). Mainly yellow. Pronotum yellow with a brownish spot on lateral side. Prescutum with three black longitudinal stripes; anterior end of lateral prescutal stripe bent outward, outer part brown. Scutum with two large, dark-brown spots. Scutellum dark yellow. Mediotergite yellow with dark-brown posterior margin. Anepisternum and katepisternum pale yellow with yellow lower part. Anepimeron pale yellow. Parascutellum pale brown; anatergite and katatergite pale yellow. Legs yellow except middle portions of femora, tips of tibiae, and tarsi dark brown; hairs dark brown, except those on coxae and trochanters yellow. Wing subhyaline, tinged with light brown; pterostigma pale brown; cell m1 nearly sessile (Fig. 18 ). Halter with stem brownish grey; knob yellowish brown.

Abdomen (Fig. 17 ). Mainly yellow. Abdominal tergites with three brown longitudinal stripes. Hypopygium mainly dark yellow. Abdomen with yellow hairs.

Hypopygium (Figs 20-25 ) brownish yellow. Tergite 9 ellipse with spade-shaped protuberance bearing two short horns at posterior margin; posterolateral margin of tergite 9 with a large jaw-shaped protuberance (Fig. 22 ). Posterior margin of sternite 8 with obvious appendages, meniscus-shaped in lateral view, covered with dense yellow hairs (Fig. 20 ). Outer gonostylus fleshy, spade-shaped, wide at middle, narrowed toward tip (Fig. 21 ). Inner gonostylus with large concavity, basally with a posterior projection (Figs 24 , 25 ).

Distribution.

China (Xizang).

Remarks.

Hypopygium of this species is very specific; no similar species.

Figures

Figures 17 - 19. Nephrotoma didyma Yang & Yang, 1987. 17 Male habitus, lateral view 18 wing 19 head and thorax, dorsal view. Scale bars: 1.0 mm.

Figures 20 - 25. Nephrotoma didyma Yang & Yang, 1987. 20 Hypopygium, lateral view 21 outer gonostylus, lateral external view 22 tergite 9, dorsal view, softened 23 hypopygium, ventral view 24 inner gonostylus, lateral external view, softened 25 inner gonostylus, lateral external view, before softened. Scale bars: 0.5 mm (20, 22, 23); 0.1 mm (21, 24, 25).