Geranomyia degenerata, Zhang, Xiao, Zhang, Zehua & Yang, Ding, 2016

Zhang, Xiao, Zhang, Zehua & Yang, Ding, 2016, Five new species of Geranomyia Haliday, 1833 (Diptera, Limoniidae) from China, Zootaxa 4154 (2), pp. 139-154 : 144-146

Geranomyia degenerata sp. nov.

Figs. 25–30

Diagnosis. Prescutum yellow to brownish yellow with three broad dark brown longitudinal stripes. Pleuron yellow with a broad brown longitudinal stripe. Wing with seven large spots on costal region; Sc1 ending about opposite 2/ 3 of Rs, basal section of CuA1 a very short distance before fork of M. Clasper of gonostylus inexistent. Lobe of gonostylus with rostral prolongation long, slender, dorsally curved, base with a long, dominant, dorsally curved spine.

Description. Male. Body length 5.5–6.5 mm, wing length 5.5–6.5 mm, mouthparts length 2.1–2.5 mm.

Head ( Fig. 26 ). Brownish black. Setae on head brownish black. Antenna length 1.1–1.2 mm, dark brown with flagellomeres slightly paler. Scape cylindrical. Pedicel nearly globose. Flagellomeres oval, terminal flagellomere with tip cuspate. Mouthparts brownish black with brownish black setae.

Thorax. Pronotum brown. Prescutum yellow to brownish yellow with three broad dark brown longitudinal stripes. Scutum pale yellow with a brown longitudinal stripe at middle area, each lobe with a large brown spot. Scutellum pale yellow with middle area brown and borders dark brown. Mediotergite brown ( Fig. 27 ). Pleuron ( Fig. 25 ) yellow with a broad brown longitudinal stripe extending from cervical region to mediotergite. Setae on thorax brownish black. Coxae and trochanters pale yellow; femora brownish yellow to pale brown with bases and tips yellow; tibiae and tarsi dark brownish yellow. Setae on legs brown. Wing ( Fig. 28 ) tinged pale brown with brown pattern: seven large spots on costal region; seams along cord, m-m and basal section of M3; a spot at fork of Rs. Veins brown, darker in clouded areas. Venation: Sc long, Sc1 ending about opposite 2/3 of Rs, Sc2 at its tip; basal section of CuA1 a very short distance before fork of M. Haltere length 0.7–0.9 mm, brownish yellow with knob pale brown.

Abdomen ( Fig. 25 ). Tergites dark brown with lateral edges darker. Sternites yellow. Setae on abdomen white.

Hypopygium ( Figs. 29–30 ). Posterior margin of tergite nine emarginate. Gonocoxite with a large and simple ventromesal lobe. Clasper of gonostylus inexistent. Lobe of gonostylus large; rostral prolongation long, slender, curved dorsally, base with a long, distinct, dorsally curved spine. Paramere with mesal-apical lobe slender and curved inwards, tip acute.

Female. Unknown.

Type material. Holotype male ( CAU), China: Guangxi, Baise, Mt. Cenwanglao, Dalongping (24°29'12"N, 106°20'55"E, 1300 m), 2012. VII.28, Yunlan Jiang . Paratypes: 4 males ( CAU), same data as holotype . 1 male ( CAU), China: Guangxi, Baise, Mt. Cenwanglao, Dalongping (24°28'4"N, 106°23'3"E, 1200 m), 2012. V.24, Guoquan Wang (light trap).

Distribution. China (Guangxi).

Etymology. The specific name (from Latin degeneratus (adj., meaning"degenerate”)) refers to the clasper of gonostylus being inexistent.

Remarks. This new species is somewhat similar to G. bifurcula ( Alexander, 1933) in having the similar body color, clouds and venation of wing, and structure of lobe of gonostylus of male hypopygium, but can be easily distinguished from the latter by the male hypopygium with posterior margin of tergite nine emarginated and the clasper of gonostylus inexistent ( Figs. 29–30 ). In G. bifurcula , the posterior margin of tergite nine is deeply and narrowly notched, and the clasper of gonostylus is small, slender and nearly straight (Alexander 1 933). This new species is also similar to G. durga (Alexander, 1967) and G. feuerborni ( Alexander, 1931) in having the similar structure of male hypopygium, but can be distinguished by the details of male hypopygium. In G. d u rg a, the mesalapical lobe of paramere has a strong lateral lobe or obtuse spine ( Alexander 1967b), which is inexistent in the new species. The rostral prolongation of lobe of gonostylus in G. feuerborni is much longer and slenderer ( Alexander 1931).

Figures

FIGURES 25 – 28. Geranomyia degenerata sp. nov. 25: Male habitus, lateral view; 26: Head, lateral view; 27: Thorax, dorsal view; 28: Wing. Scale bar: 25 = 1.0 mm; 26 – 27 = 0.5 mm; 28 = 1.0 mm.

FIGURES 29 – 30. Geranomyia degenerata sp. nov. 29: Male hypopygium, dorsal view; 30: Male hypopygium, ventral view. Scale bar: 29 – 30 = 0.2 mm.