Polypedilum (Tripodura) conghuaense Zhang & Wang

Zhang, Ruilei, Song, Chao, Qi, Xin & Wang, Xinhua, 2016, Taxonomic review on the subgenus Tripodura Townes (Diptera: Chironomidae: Polypedilum) from China with eleven new species and a supplementary world checklist, Zootaxa 4136 (1), pp. 1-53 : 13-14

Polypedilum (Tripodura) conghuaense Zhang & Wang sp. n.

( Figure 5 )

Polypedilum sp 7. SC_song128, 129, 130; Song et al. 2016: 542.

Type material. Holotype: male (ZRL. 00377), CHINA: Guangdong Province, Guangzhou City, Conghua District, River Liuxi, 26. X. 2014, light trap, C. Song. Paratypes: 10 males as the holotype. 2 males (deposited in Jinan University, Guangzhou, China), Guangdong Province, Guangzhou City, Conghua District, River Liuxi, 25. X. 2014, light trap, H. Tang.

Etymology. Named after the type locality, Conghua District.

Diagnostic characters. Differs from other members of the subgenus by the extremely reduced anal point elongation and very small body size.

Male imago (n=7, when otherwise stated)

Total length 1.50–1.86, 1.72 mm (5). Wing length 0.90–0.96, 0.94 mm. Total length/ wing length 1.67–1.94, 1.84. Wing length/ length of profemur 2.50–2.74, 2.59.

Coloration. Head brown. Thorax yellowish brown with dark brown vittae, postnotum and preepisternum. Abdominal segments yellowish brown. Femur brown with pale sub-apical ring, the remaining parts of legs yellowish brown.

Head. AR 0.74–0.77, 0.76 (4). Ultimate flagellomere 250–265, 256 µm (4) long. Temporal setae 6–8, 7, including 3–3, 3 inner verticals, 1–3, 2 outer verticals and 2–3, 2 postorbitals. Clypeus with 8–12, 10 setae. Tentorium 65–78, 73 µm long, 15–18, 17 µm wide; Stipes 65–75, 71µm long. Palpomere lengths (in µm): 20–28, 24; 20–25, 23; 43–53, 49; 60–75, 70; 95–105, 100. 3rd palpomere with 1 sensillum.

Wing ( Figure 5A ). Wing with several markings, two in cell r4+5, one in middle of cell m, one in cell m1+2, one at base of cell m3+4 and extended across vein Cu1, wing distal margin also with grey tract. VR 1.30–1.39, 1.33. R with 8–10, 9 setae; R1 with 2–5, 3; R4+5 with 1–3, 2 setae. Squama with 2–3, 3 setae.

Thorax. Dorsocentrals 6–10, 8; acrostichals 7–11, 10; prealars 2–3, 3. Scutellum with 2–2, 2 setae.

Legs. Terminal scale ( Figure 5B ) of front tibia 18–25, 23 µm long, triangular with a small spur. Spur of middle tibia 28–33, 31 um long including 15–18, 17 µm long comb, un-spurred comb 13–18, 16 µm long, spur of hind tibia 25–38, 32 µm long including 15–23, 18 µm long comb, un-spurred comb 15–23, 17 µm long. Width at apex of front tibia 25–30, 28 µm, of middle tibia 25–33, 28 µm, of hind tibia 25–35, 31 µm. Lengths (in µm) and proportions of legs as in Table 1 .

Hypopygium ( Figure 5C, D ). Anal tergite band weak, not fused at base. Tergite IX with 6–9, 8 median setae. Laterosternite with 1–2, 1 seta. Anal point elongation extremely reduced, distal margin with 8–9 flattened setae. Phallapodeme 38–48, 45 µm long, transverse sternapodeme 12–16, 13 µm long. Gonocoxite 68–70, 69 µm long. Superior volsella ( Figure 5C ) 23–28, 25 µm long, entirely pubescent, anteromedially bent. Inferior volsella 38–45, 40 µm long, with 9–10 oral setae and 1 apical seta. Gonostylus 65–73, 70 µm long, with 4 long setae along inner margin. HR 0.93–1.00, 0.98. HV 2.31–2.55, 2.45.

Distribution. The species was collected from the Oriental China.

Figures

FIGURE 5 A – D. Polypedilum (Tripodura) conghuaense Zhang & Wang sp. n. A. Wing. B. Fore tibial scale. C. Superior volsella. D. Hypopygium, dorsal and ventral view.