Polypedilum (Uresipedilum) cultellatum Goetghebuer, 1931

Zhang, Ruilei & Wang, Xinhua, 2004, Polypedilum (Uresipedilum) Oyewo and Saether from China (Diptera: Chironomidae), Zootaxa 565 (1), pp. 1-38 : 14-17

Polypedilum (Uresipedilum) cultellatum Goetghebuer

( Fig. 6 )

Polypedilum cultellatum Goetghebuer, 1931: 212 ; Brundin 1947: 64; Pinder 1978: 37. Sasa & Hasegawa 1983: 330.

Polypedilum (Polypedilum) cultellatum: Rossaro, 1985: 21 ; Niitsuma, 1992: 696.

Polypedilum subcultellatum Sublette, 1960: 204 .

Microtendipes ureshinoense Sasa, 1979: 19 .

Polypedilum ureshinoense: Sasa 1980: 37 .

Polypedilum (Uresipedilum) cultellatum: Oyewo & Saether, 1998 ; Maschwitz & Cook, 2000: 63. Wang, 2000:646.

Material examined: CHINA: 2 male, Tianjin City, Ji County, Yuqiao Reservoir , 20. X. 1986, X. Wang . 1 male, Hebei Province, Qianxi County, Daheiting Reservoir , 25. IX. 2001, R. Zhang, sweep net . 3 males, Fujian Province, Yongtai County; 16. 19. IX. 2002, Z. Liu . 1 male, Fujian Province, Daiyun Mountains Natural Conservation, Houzhai Village ; 15. IX, 2002; Z. Liu . 1 male, Fujian Province, Shanghang County, Buyun Town , 7. V. 1993, X. Wang . 1 male, Guangdong Province, Shenzhen City, Lianhuashan Park , 18. V. 2002, R. Zhang . 1 male, Hainan Province, Lingshui County, Diaoluo Town , 20. V. 1988, X. Wang . 2 males, Taiwan Province, Guandu Natural Conservation , 23. VI. 1988, C. Maa . 1 male, Guizhou Province, Luodian County, 420m, 7. VIII. 1995, W. Bu . 2 males, Sichuan Province, Chengdu City , 16. V. 1986, W. Bu . 1 male, Xizang Autonomous region (Tibet), Zham County, Yiliang ; 18. IX. 1987, C. Deng .

Diagnostic characters: The presence of 2–5 apical setae on the superior volsella and the short, narrow and tapering anal point will separate the species from other members of the subgenus.

Male imago (n = 15, except when otherwise stated)

Total length 2.47–3.89, 3.17 mm. Wing length 1.33–2.24, 1.73 mm. Total length/ wing length 1.53–2.09, 2.05. Wing length /length of profemur 1.86–2.54, 2.05.

Coloration. Variable in coloration. Head yellow or brown. Thorax entirely yellow or brown, or yellow with brown postnotum or brown with darker vittae and postnotum, legs yellow except brown fore tibiae and tarsi. Abdominal segments entirely yellow or brown.

Head. AR 1.30–1.76, 1.52. Temporal setae 8–15, 12(14); including 2–5, 4(12) inner verticals; 2–8, 5(12) outer verticals and 2–4, 3(14) postorbitals. Clypeus with 13–25, 18 setae. Tentorium 100–143, 126(10) m long, 23–44, 33(10) m wide. Palpomere lengths (in m): 34–47, 36(14); 39–57, 45(14); 78–117, 100(14); 88–112, 102(14); 110–205, 171(14).

Wing ( Fig. 6A ). VR 1.18–1.39, 1.23. Brachiolum with 1 setae, R with 18–30, 23; R 1 with 12–20, 15(14); R 4+5 with 18–35, 26. Squama with 7–11, 9 setae.

Thorax. Dorsocentrals 11–19, 15(14); acrostichals 9–17, 12(13); prealars 4–7, 5. Scutellum with 9–20, 12(13) setae.

Legs. Terminal scale ( Fig. 6B ) of front tibia 23–44,36 m long with small spine; spur on median tibiae 50–65, 56 µm long including 23–34, 29 m long comb, un­spurred comb 21–36, 26 m long, spur on posterior tibia 49–73, 60 m long including 25–34, 30 m long comb, un­spurred comb 23–34, 28 m long. Width at apex of front tibia 38–62, 54(13) m, of middle tibia 38–57, 51(13) m, of hind tibia 48–62, 56(13) m. Lengths (in m) and proportions of legs (Table 6):

Hypopygium ( Figs. 6C–K ). Anal tergite bands weak not fused basal to median anal tergite setae. Anal tergite with 3–11, 7 median setae, laterosternite with 2–4, 3 setae. Anal point narrow, relatively short and tapering apically. Phallapodeme 75–122, 97 m (14) long; transverse sternapodeme 28–50, 37 m (11) long. Gonocoxite 125–190, 157 m long. Superior volsella 38–55, 46 m long, moderately to strongly projected posteriorly, base with 0–2 inner setae and 3–5 apical setae, microtrichiae present; apicomedial projection 28–43, 33 m long. Inferior volsella 88–109, 99 m long, swollen subapically with 10–16 oral setae and 1 apical seta. Gonostylus 123–180, 152 m long. HR 0.85–1.17, 1.04. HV 1.75–2.46, 2.10.

Distribution: The species is widely distributed in the Holarctic region. It occurs in both Palaearctic and Oriental China. This is the first record from the Oriental Region.

Remarks: Niitsuma (1992) mentioned that he had cultured an egg­mass of this species and examined 71 reared adult males. He found that about 90% males had 2–3 apical setae on the superior volsella while 10% had 45 apical setae. The size of the apicomedial projection varied between individuals and had no relationship to the number of apical setae.

Maschwitz and Cook (2000) regarded P. subcultellatum as a synonym of P. cultellatum . Sublette (1964) noted P. subcultellatum having yellow brown thorax with dark vittae and postnotum, abdominal tergites light brown, posterior third of tergites I–VI shade darker; inferior volsella not widened, gonostylus short and widest at base. Niitsuma (1992) described the species largely yellow to yellowish green with dark or dark brown vittae, postnotum and preepisternum; inferior volsella swollen subapically, gonostylus nearly parallel­sided and widest in the middle. Among examined material from China, the specimens collected in Tianjin and Sichuan resemble P. subcultellatum in body coloration, remaining specimens identical to the description of Niitsuma (1992). The inferior volsella of all Chinese specimens is subapically swollen. The only exception is the material from Tianjin without inner seta ( Fig. 6F ) and with a much stronger apicomedial projection on the superior volsella.

Figures

FIGURE 6. Polypedilum (Uresipedilum) cultellatum Goetghebuer, Chinese specimen. A.Wing. B. Fore tibia scale. C–G. Superior volsella. H. J. Dorsal view of hypopygium. I. K. Ventral view of hypopygium.