Tipula (Vestiplex) quadricorna, Ren & Li & Yang, 2021

Ren, Jinlong, Li, Yan & Yang, Ding, 2021, Two new species of Tipula (Vestiplex) Bezzi (Diptera, Tipulidae) from Northwest China, Zootaxa 4903 (3), pp. 373-392 : 381-384

Tipula (Vestiplex) quadricorna sp. nov.

( Figs 22–32 )

urn:lsid.zoobank.org/ C156CA2D-F373-403C-87AE-EF49C5D0446F

Diagnosis. Antenna 13-segmented, reaching beyond base of abdomen if bent backward. Tubercle on vertex low with one narrow dark stripe at middle. Pronotum with two round yellow spots. Costal and subcostal cells brown. Posterior margin of tergal saucer with a deep narrow median notch; anterior part of tergal saucer elevated into a sclerotized plate with four protrusions. Posterior margin of tergite 9 with a long tongue-shaped proctiger. Gonocoxite elongated into a long and raised lobe which bears a strongly sclerotized process at middle. Clasper of gonostylus curved, blade-shaped, point-apexed. Anterior immovable apodeme (aia) of semen pump small, triangular.

Material examined. Type specimens 3 males.

Holotype: male, Ningxia, Jingyuan, Liupan Mountain, Dongshanpo , 35.62°N, 106.28°E, alt. 2000 m, 2008. VI.26, Yongjie Wang.

Paratypes: 1 male, Ningxia, Jingyuan, Liupan Mountain, Dongshanpo , 35.62°N, 106.28°E, alt. 2100 m, 2008. VI.21, Gang Yao ; 1 male, Ningxia, Jingyuan, Liupan Mountain, Dongshanpo , 35.62°N, 106.28°E, alt. 2180 m, 2008.VI.22, Tingting Zhang .

Description. Male (N= 3): body length 18–19 mm, wing length 18–20 mm, antenna length 5–6 mm.

Head. Mostly greyish pruinose. Vertex with some dark bristles along eye margin. Tubercle on vertex low with one narrow dark stripe at middle. Occiput grey with a pale brown median stripe. Rostrum and nasus brown.Antenna 13-segmented, reaching beyond base of abdomen if bent backward; scape and pedicel yellow; first flagellomere yellowish-brown, remaining segments dark brown ( Figs 22, 23 ). Palpus brown.

Thorax. Mostly brownish-grey. Pronotum with two round yellow spots ( Fig. 22 ). Prescutum and presutural scutum with four stripes, lateral pair more greyish than median pair, bearing narrow dark brown margins. Scutal lobe with two circular spots which have greyish-brown center and dark brown margin. Scutellum grey pruinose with a narrow brown stripe at middle. Mediotergite grey pruinose with one broad brown stripe at middle ( Fig. 23 ). Mesopleuron entirely grey pruinose. Legs with coxae greyish-brown; trochanters yellowish; femora and tibiae brown with dark brown tips; tarsi dark brown ( Fig. 22 ); formula of tibial spurs 1–2–2. Wing whitish subhyaline, variegated with dark brown; costal and subcostal cells brown; stigma dark brown; dark brown marking along fork of R s to cross vein r-m; whitish area forming a large C-shaped marking at bases of cells r 1+2, r 3, r 4, r 5, d and m 3; another whitish area forming a C-shaped marking along median Rs, median base of cell m and apex of cell cua ( Fig. 24 ). Halter with stem yellow, knob dark brown.

Abdomen ( Fig. 22 ). Mainly light yellow. Tergites 1–4 with one dark brown middle longitudinal stripe. Abdominal segments 6–8 dark brown. Setae on abdomen blackish or dark yellow.

Hypopygium. Tergite 9 shaped as an extremely large concave sclerotized tergal saucer. Posterior margin of tergal saucer nearly truncated, with a deep narrow median notch, which divided into two somewhat rectangular lobes posteriorly; anterior part of tergal saucer elevated into a sclerotized plate with four protrusions ( Figs 25, 26 ). Posterior margin of tergite 9 with a long tongue-shaped proctiger which is hollow and round apexed ( Fig. 26 ). Tergite 9 and sternite 9 fused into a continuous ring ( Fig. 25 ). Sternite 9 divided into two lobes by a median split ( Fig. 27 ). Gonocoxite elongated into a long and raised lobe, which bears a strongly sclerotized process at middle ( Figs 25, 29 ). Lobe of gonostylus rod-shaped and setose ( Fig. 29 ). Clasper of gonostylus curved blade-shaped, with a sharp beak ( Fig. 28 ).

Semen pump. Dark brown. Posterior immovable apodeme (pia) rod-shaped and point-apexed ( Figs 30–32 ); compressor apodeme (ca) fan-shaped and directed downward, forming a 65° angle with posterior immovable apodeme; anterior immovable apodeme (aia) small, triangular ( Fig. 32 ).

Female. Unknown.

Elevation range in China. Adults were collected at altitudes ranging from 2000 m to 2200 m.

Period of activity. Adults were collected only in late June.

Distribution. China (Ningxia).

Etymology. The specific name (from Latin quadri (adj., meaning “four”) and Latin cornis (adj., meaning “horny”) refers to four protrusions at the anterior margin of tergal saucer.

Remarks. This new species is similar to T. (V.) tchukchi Alexander, 1934 in the shape of tergite 9. It can be separated from the latter by following features: posterior margin of tergal saucer divided into a pair of approximately rectangular lobes which have smooth and transverse margins; gonocoxite elongated into a long lobe. In T. (V.) tchukchi the posterior lobes of tergal saucer have serrated and oblique margins; gonocoxite unarmed ( Alexander, 1934; Mannheims, 1967).

Figures

FIGURES 22–24. Tipula (Vestiplex) quadricorna sp. nov. 22: male habitus, lateral view; 23: head and thorax, dorsal view; 24: right wing. Scale bars 1.0 mm.

FIGURES 25–29. Tipula (Vestiplex) quadricorna sp. nov. 25: hypopygium, lateral view; 26: tergite 9 and proctiger, dorsal view; 27: hypopygium, ventral view; 28: clasper of gonostylus; 29: lobe and clasper of gonostyli with apex of gonocoxite, lateral view. Scale bars: 0.5 mm (25–27), 0.1 mm (28, 29).

FIGURES 30–32. Tipula (Vestiplex) quadricorna sp. nov. 30: semen pump, dorsal view; 31: semen pump, ventral view; 32: semen pump, lateral view. Scale bars 0.1 mm.