Rhipidia (Rhipidia) bilobata, Zhang, Xiao, Li, Yan & Yang, Ding, 2014

Zhang, Xiao, Li, Yan & Yang, Ding, 2014, A review of the genus Rhipidia Meigen from China, with descriptions of seven new species (Diptera, Limoniidae), Zootaxa 3764 (3), pp. 201-239 : 209-211

Rhipidia (Rhipidia) bilobata sp. nov.

( Figs. 16–22 )

Diagnosis. Male antenna with nine bipectinate flagellomeres. Pleuron brown with two conspicuous brownish black longitudinal stripes. Wing grayish white with numerous small pale gray spots and some darker spots; Sc1 ending near midlength of Rs; basal section of CuA1 proximad of fork of M. Lobe of gonostylus with seven rostral spines.

Description. Male. Body length 4.6 mm, wing length 5.0 mm.

Head (fig. 17). Brownish black, dusted with grayish white. Hairs on head brownish black. Antenna 1.3 mm long. Scape and pedicel brown, flagellomeres one to ten pale yellow with basal enlargements and branches brownish yellow, remaining flagellomeres brownish yellow. First flagellomere stout basally; each of flagellomeres two to ten inclusive with two branches which are the longest at fourth or fifth flagellomere and about twice as long as corresponding flagellomere; eleventh flagellomere enlarged but not pectinate; terminal flagellomere longated, exceeding penultimate. Labellum and palpus dark brown with brown hairs.

Thorax (fig. 16). Generally brown, dusted with grayish white. Pronotum brown. Prescutum brown with three brownish black stripes. Scutum brown, middle area paler, each lobe with pale yellow spot. Scutellum brown. Mediotergite brown to brownish black. Pleuron brown with two brownish black longitudinal stripes, upper one extending from cervical region to base of abdomen, lower one extending from fore coxa to hind coxa. Hairs on thorax white. Coxae brownish yellow; trochanters pale yellow. Wing (fig. 18) grayish white; all cells with numerous small pale gray spots; larger and darker spots at base of cell Sc, middle area of cell Sc, origin of Rs, fork of Sc, fork of Rs and tip of R1; veins pale yellow, darker in clouded areas. Venation: Sc1 ending near midlength of Rs, Sc2 near its tip; basal section of CuA1 proximad of fork of M. Halter 0.7 mm long, white with knob slightly darker.

Abdomen (fig. 16). Tergites and sternites brownish yellow. Hairs on abdomen white.

Hypopygium (figs. 20–22). Posterior margin of tergite nine with deep V-shaped notch, forming two broadly rounded lobes. Gonocoxite with a single simple ventromesal lobe. Clasper of gonostylus arched at 2/3 length, suddenly narrowed to apical spine. Lobe of gonostylus large; rostral prolongation small with seven spines immediately beyond midlength, lengths of spines very unequal, longest one about three times as long as shortest. Paramere with mesoapical lobe blackened, tip acute.

Female. Unknown.

Type material. Holotype male ( CAU), China: Tibet, Motuo, Beibeng (700 m), 2011. VII. 20, Wenliang Li.

Distribution. China (Tibet).

Etymology. The specific epithet is an adjective and refers to the two broadly rounded lobes formed by posterior margin of tergite nine with deep V-shaped notch (from Latin bilobatus meaning “bilobate”).

Remarks. This new species is somewhat similar to R. (R.) chenwenyoungi Zhang, Li and Yang, 2012 from China in having similar clouds and venation of wing, but it can be easily distinguished from the latter by the male antenna with nine bipectinate flagellomeres (fig. 17), the pleuron being brown with two conspicuous brownish black longitudinal stripes (fig. 16), and the male hypopygium with seven very unequal rostral spines (figs. 20–22). In R. (R.) chenwenyoungi , the male antenna has eight bipectinate flagellomeres, the pleuron is brownish yellow with a conspicuous brownish black longitudinal stripe, and the male hypopygium has six rostral spines. In addition, it is somewhat similar to another new species, R. (R.) spinosa sp. nov., in having a similar hypopygium, but it can be easily distinguished from the latter by the posterior margin of tergite nine with deep V-shaped notch, forming two broadly rounded lobes (figs. 19, 21). In R. (R.) spinosa sp. nov., the posterior margin of tergite nine is gently emarginated (fig. 79).

Figures

FIGURES 16 – 19. Rhipidia (Rhipidia) bilobata sp. nov. 16: Habitus of male, lateral view; 16: Head of male, lateral view; 18: Wing; 19: Tergite nine of male. Scale bar: 16 = 2.0 mm; 17 = 0.5 mm; 18 = 1.0 mm; 19 = 0.2 mm.

FIGURES 20 – 22. Rhipidia (Rhipidia) bilobata sp. nov. 20: Hypopygium, lateral view; 21: Hypopygium, dorsal view; 22: Hypopygium, ventral view. Scale bar: 20 – 22 = 0.2 mm.