Polypedilum (Uresipedilum) bullum, Zhang & Wang, 2004

Zhang, Ruilei & Wang, Xinhua, 2004, Polypedilum (Uresipedilum) Oyewo and Saether from China (Diptera: Chironomidae), Zootaxa 565 (1), pp. 1-38 : 7-9

Polypedilum (Uresipedilum) bullum sp. n.

( Fig. 3 )

Type material: Holotype male ( BDN No. 13415): CHINA: Sichuan Province, Xiangcheng County, Shuoqu River , 12, 2700m, 12. VI. 1996, X. Wang.

Etymology: From Latin bulla, knob, refers to a prominent knob at the base of the superior volsella, which is unusual in the subgenus.

Diagnostic characters: Differs from the other species of the subgenus in having a prominent inner process basally on the superior volsella, wing with weak markings, and inferior volsella apically divided into two lobes.

Male imago (n = 1)

Total length 4.00 mm. Wing length 2.65 mm. Total length/ wing length1.51. Wing length /length of profemur 2.58.

Coloration. Head brown. Thorax brown with darker vittae and postnotum. Abdomen and legs brown. Wings brown with weak marking.

Head. AR 1.24. Ultimate flagellomere 662 m long. Temporal setae 12; including 3 inner verticals; 5 outer verticals and 4 postorbitals. Clypeus with 15 setae. Tentorium 159 m long, 47 m wide. Stipes 169 m long. Palpomere lengths (in m): 44, 47, 177, 172, 292.

Wing ( Fig. 3A ). VR 1.10. Brachiolum with 1 seta, R with 22; R 1 with 14; R 4+5 with 27. R 2+3 near to R 1. Squama with 15 setae. Wing with weak markings.

Thorax. Dorsocentrals 22; acrostichals 15, biserial; prealars 5. Scutellum with 22 setae.

Legs. Terminal scale ( Fig. 3B ) of front tibia pointed, 52 m long including 16 m long apical spine; spur on median tibiae 42 µm long including 29 m long comb, un­spurred comb 23 m long, spur on posterior tibia 47 m long including 31 m long comb, unspurred comb 23 m long. Width at apex of front tibia 56 m, of middle tibia 60 m, of hind tibia 65 m. Lengths (in m) and proportions of legs ( Table 3):

Hypopygium ( Figs. 3C–E ). Anal tergite bands fused basal to median anal tergite setae. Anal tergite with 10 median setae, laterosternite with 3 setae. Anal point 94 m long, slender and parallel­sided for entire length, ventrally bent at apex. Phallapodeme 117 m long; transverse sternapodeme 70 m long. Gonocoxite 198 m long. Superior volsella 52 m long, base not produced caudally with microtrichiae and 12 long apical setae, a prominent process bearing 12 inner setae basely present in the inner margin of the base; apicomedial projection slender and rounded at apex. Inferior volsella 143 m long; apically divided into 2 lobes, with 12 oral setae and long apical seta respectively. Gonostylus 140 m long, outer margin convex widest in the middle. HR 1.41. HV 2.85.

Distribution: The species was collected by light trap near a river in the Sichuan Province in the Oriental Region.

Remarks: In the examined specimen, the prominent inner process of one superior volsella bears one seta, while the other has two setae; the base of one of the superior volsellae one apical seta, the other two apical setae. In the subgenus, only one species, P. (U.) simantokeleum Sasa has a superior volsella with an inner basal process, but that species is distinctly differing from the new species in several other features.

Figures

FIGURE 3. Polypedilum (Uresipedilum) bullum sp. n. A.Wing. B. Fore tibia scale. C. Superior volsella. D. Dorsal view of hypopygium. E. Ventral view of hypopygium.