Rhaphium dorsiseta, Tang, Chufei, Wang, Ning & Yang, Ding, 2016

Tang, Chufei, Wang, Ning & Yang, Ding, 2016, Rhaphium (Diptera: Dolichopodidae: Rhaphiinae) from China with six new species, Zootaxa 4162 (3), pp. 581-593 : 589-591

Rhaphium dorsiseta sp. nov.

( Figs 5 , 15–17 )

Diagnosis. First flagellomere 2.0 times longer than wide. 5 dc; 6 irregular pairs of short acr ( Fig. 15 ). Fore tarsomere 5 with 2 Y-shaped dorsoapical bristles and 2 long strong bristles ( Fig. 17 ). Cercus long linear and hooked, somewhat inflated apically with 1 apical bristle. Phallus simple except one spine-like dorsal process ( Fig. 16 ).

Description. Male ( Fig. 5 ). Body length 5.0 mm, wing length 4.5 mm. Head: Frons metallic green with grey white pollinosity; face dark metallic green with thick silvery white pollinosity; palpus and proboscis black with black hairs; antenna black; first flagellomere nearly isosceles triangular, rounded at tip, 2.0 times longer than wide; arista apical, simple, with microscopic hairs, 1.8 times as long as first flagellomere ( Fig. 15 ). Thorax metallic green with grey white pollinosity, propleuron with short pale yellow dense hairs, metapleuron yellowish brown at lower portion; hairs and bristles strong and black; 5 dc; 6 irregular pairs of short acr; median sc normal, lateral sc weak and short. Legs yellow except base of fore coxa, mid and hind coxae black, apical 1/4 of hind femur black dorsally, hind tibia yellow to black at apical 1/2; fore and mid tarsi brown to dark brown from tip of first tarsomere onwards, hind tarsus black. Hairs and bristles on legs mainly black, fore coxa with pale yellow hairs, fore and mid coxae with 1 black bristle at apical 1/3, hind coxae with 1 strong black coxae at middle. Fore tibia with 3 ad, mid tibia with 4 ad, 4 pd and 3 apical bristles; hind tibia with 2 ad and 3 pd. Fore tarsomere 5 with 2 Y-shaped dorsoapical bristles and 2 long strong bristles ( Fig. 17 ). Relative length ratio from tibia to tarsomere 5: LI: 1.5/0.5/ 0.4/0.3/0.2/0.3, LII: 3.5/2.0/?/?/?/?, LIII: 5.0/1.5/1.6/1.0/?/? (mid and hind tarsi broken). Wing hyaline, brownish; veins dark brown, R4+5 and M somewhat convergent apically; CuAx ratio 0.5. Squama yellow, with fan of pale bristles; halter yellow. Abdomen metallic green with grey white pollinosity. Bristles and hairs black. Black bristles on first segment dorsally and pale yellow hairs on segments 2–5 laterally and sternites 1–4, with 2 curved black bristles apically on 4th segment laterally. Male genitalia ( Fig. 16 ): epandrium nearly as long as wide, epandrial lobes indistinct. Surstylus with 1 deep incision at middle, apical 1/3 finger-like, with some short lateral hairs and 1 pale yellow rod-like apical bristle. Cercus long linear and hooked, with spine-like black bristles at middle, somewhat inflated apically with 1 apical bristle. Hypandrium with an incision ventrally and a process dorsally. Phallus simple except one spine-like process dorsally. Female. Unknown.

Type material. HOLOTYPE, Ƌ labeled: China: Inner Mongolia, Daqinggou, Primeval forest (N42°82′18″ E122°17′41″), 180 m, collected by sweeping net in grass and brushes, 2015. VII.7, C. Tang ( CAU).

Distribution. Palaearctic: China (Inner Mongolia).

Remarks. The new species is somewhat similar to R. qinghaiense Yang, 1998 from Qinghai province of China, but may be separated from the latter by the length / width ratio of the first flagellomere, the bristles on the fore tarsomere 5 and the shape of the cercus. In R. qinghaiense , the first flagellomere is 5.9 times longer than wide; the bristles on fore tarsomere 5 are normal and the cercus is long, thinner onwards ( Yang et al. 2011).

Etymology. The word ‘ dorsiseta ’ means dorsal bristle, refers to the dorsoapical bristle of fore tarsomere 5.

Figures

FIGURE 1 – 6. 1. Rhaphium apophysatum sp. nov.; 2. R. bilobum sp. nov.; 3. R. bisectum sp. nov.; 4. R. daqinggouense sp. nov.; 5. R. dorsiseta sp. nov.; 6. R. neimengense sp. nov. All male. Scale bar = 1.0 mm.

FIGURES 15 – 17. Rhaphium dorsiseta sp. nov., male. 15. Antenna, scale bar = 0.2 mm; 16. Male genitalia, lateral view, scale bar = 0.2 mm. 17. Male fore tarsomere 5. v Abbreviations: hyp = hypandrium, epl = epandrial lobe, ph = phallus, sur = surstylus, cer = cercus.