Neurigona sichuana Wang, Chen & Yang, 2010

Wang, Mengqing, Chen, Hongyin & Yang, Ding, 2010, New species of the genus Neurigona (Diptera: Dolichopodidae) from China, Zootaxa 2517 (1), pp. 53-61 : 56-58

Neurigona sichuana Wang, Chen & Yang sp. nov.

( Figs. 4–7 )

Diagnosis. Scutellum brownish. Seven strong dc bristles, 11–12 irregularly paired acr bristles. Tarsomere I 4 short, with basal half swollen and apical half concave ventrally, tarsomere I 5 with basal 1/4 swollen and middle portion concave ventrally. Abdominal segment 5 without ventral projection.

Male. Body length 4.5–4.7 mm, wing length 4.0– 4.2 mm.

Head metallic green with pale gray pollen; face narrow, eyes separate on face. Setae and bristles on head black; postocular bristles pale. Antenna yellow ( Fig. 5 ); first flagellomere about 1.2 times longer than wide, somewhat acute apically; arista brown with basal segment 0.1 times as long as apical segment. Proboscis brownish yellow with pale hairs; palpus pale yellow, with pale setae.

Thorax yellow with yellow pollen; scutellum (except posterior margin) and metanotum brownish; pteropleuron with small black spot just below wing base. Setae and bristles on thorax black, but those on pronotum and propleuron yellow; 7 strong dc bristles, 11–12 irregularly paired acr bristles. Propleuron with 1 yellow bristle on lower portion. Legs yellow; coxae I-III yellow. Setae and bristles on legs black. Coxa I with black setae and black bristles on apical portion. Coxa III with 1 black outer bristle near middle. Tibia II with 3 ad bristles, 2 pd bristles, and 1-2 v bristles, apically with 3 bristles; hind tibia with 3 ad bristles, 3 pd bristles, and 3-4 v bristles, apically with 4 bristles. Tarsomere I 4 short (about 2/3 of tarsomere I 5 in length), with basal half swollen and apical half concave ventrally, tarsomere I 5 with basal 1/4 swollen and middle portion concave ventrally ( Fig. 6 ). Tarsomere II 1 with 1 ad bristle and 4–6 short black v bristles; tarsomeres III 1–3 each with row of short v bristles, tarsomere III 4 with 5 short v bristles, tarsomere III 5 with 1-2 short v bristles. Relative lengths of tibia and 5 tarsomeres of legs LI 4.6: 4.2: 2.0: 0.8: 0.5: 0.8; LII 4.0: 4.1: 1.2: 1.0: 0.5: 0.4; LIII 6.2: 1.7: 2.2: 1.2: 0.8: 0.4.

Wing ( Fig. 4 ) hyaline with grayish; veins black, M 1+2 strongly bent apically and convergent with R 4+5; CuAx ratio 0.5. Squama yellow with pale hairs. Halter yellow.

Abdomen yellow with yellow pollen; terga 2–4 each with large black basal spot; hypopygium shiny black. Abdominal segment 5 without ventral projection. Setae on abdomen chiefly black.

Genitalia ( Fig. 7 ). Epandrium somewhat round, basally with 2 slender processes. Surstylus with dorsal lobe wide, with acute apex; ventral lobe long and curved apex, with apical hairs. Cercus white, with wide base and slender apex.

Female. Body length 5.3-5.5 mm, wing length 4.8-4.9 mm. Similar to male, fore tarsus normal.

Type Material. Holotype: male, Sichuan: Leshan, Lvxin , 2009.VIII.18, Yan Li . Paratypes: 2 males and 4 females, same data as holotype . Holotype and paratypes deposited in CAU.

Etymology. The specific epithet derives from the type locality in Sichuan.

Distribution. Known only from the type locality in Sichuan.

Remarks. The species is similar to Neurigona concaviuscula Yang , but can be separated from the latter by the 11–12 irregularly paired acr, and the fore tibia lacking ad bristles. In N. concaviuscula , there are 17-18 irregularly paired acr, and the fore tibia has 1 ad bristle.

Figures

FIGURES 4–7. Neurigona sichuana sp. nov. (male). 4. Wing. 5. First flagellomere and arista. 6. Fore tarsomeres 2-5, lateral view. 7. Genitalia, lateral view. C—cercus; H—hypandrium; LP—lateral process; SDL—surstylus dorsal lobe; SVL—surstylus ventral lobe. Scale bar = 0.25 mm.