Natarsia nugax (Walker)

Cheng, Ming & Wang, Xinhua, 2006, Natarsia Fittkau (Diptera: Chironomidae: Tanypodinae) from China, Zootaxa 1111, pp. 59-67 : 60-63

Natarsia nugax (Walker)

(Figs.1–6)

Chironomus nugax Walker, 1856:186

Macropelopia curvinervis Kieffer, 1918:168 Macropelopia rectinervis Kieffer, 1918:169 Macropelopia subtenuis Kieffer, 1918: 13

Tanypus flavipubescens Goetghebuer,1921: 64 –65 Anatopynia nugax Edwards, 1929: 298

Macropelopia nugax Goetghebuer, 1936: 21 –22 Natarsia nugax Fittkau, 1962: 162 –163

Material examined. CHINA: Guizhou Province, Daomai County, Dashahe River Natural Conservation, 1 male, 30 v 2004, light trap, H. Q. Tang (BDN No.21863). Neimengguo Autonomous Region, 1 male, light trap, H. H. Li (BDN No.01593). Guizhou Province, Faning Mountain Natural Conservation, Huguo Temple, 1 male, 2 viii 2001, light trap, R. L. Zhang (BDN No.14664). Fujian Province, Dehua County, Daiyun Mountain, 1 male, 12 ix 2002, light trap, Z. Liu (BDN No.20150). Taiwan Province, 1 male (BDN No. 14591).

FIGS. 1–6. Natarsia nugax (Walker) male. 1, abdomen. 2, wing. 3, tibial spur and tibial comb on fore leg. 4, tibial spurs on mid leg. 5, tibial spur and tibial comb on hind leg. 6, hypopygium; dorsal view on left, ventral view on right.

Diagnostic characters: This species differs from known species of the genus Natarsia by having a banded abdomen and characteristic wing markings.

Male imago (n = 5)

Total length 3.59–4.18, 3.85 mm. Wing length 1.99–2.45, 2.18 mm. Total length/wing length 1.70–1.84, 1.77. Wing length/length of profemur 1.74–2.28, 2.02.

Coloration. Head including antenna brown. Thorax almost uniformly brown, vittae not distinct. Abdomen bright brown. Tergites II–V each with narrow brown basal band; tergites VI–VII nearly completely brown; tergites VIII–IX brown. Hypopygium brown. (Fig. 1). Wings with distinct pigmented area around crossvein r­m. (Fig. 2).

Head. AR 1.63–1.75, 1.68. Temporal setae 19; including 16 verticals and 3 postorbitals. Clypeus with 8–25, 13 setae. Tentorium 150–180, 162 µm long; 48–63, 56 µm wide. Palpomere 1–5 lengths (µm): 45–50, 47; 55–70, 63; 105–120, 110; 150–200, 177; 235–280, 253.

Wing (Fig. 2). VR 0.88–0.94, 0.92. Brachiolum with 3 long setae. Squama with 19–29, 23 setae. C extension 120–190, 130 µm long.Thorax. Antepronotal setae 5–9, 7. Dorsocentrals 20–36, 31; acrostichals 20–28, 24; prealars 27–84, 43; scutellars 8–12, 10; preepisternals 2–9, 5; anepisternals 1–3, 2; postnotals 2–2, 2.

Legs. Spur on fore tibiae 43–63, 54 µm long with 8 lateral teeth; apex of fore tibiae with light comb of 6 setae (Fig. 3). Spur on mid tibiae 50–63, 56 and 63–80, 71 µm long with 9 and 11 lateral teeth respectively (Fig. 4). Spur on hind tibiae 58–65, 62 and 75–95, 86 µm long with 9 and 8 lateral teeth respectively; tibial comb on hind leg of 9 setae (Fig. 5). Lengths (µm) and proportions of legs (hind tarsi of specimen No. 14664, all tarsi of specimen No.01593 and 14591 were lost) as in Table 1 .

Hypopygium (Fig. 6). Gonocoxite 163–215, 191 µm long. Gonostylus 128–153, 139µm long. HR 1.25–1.46, 1.37. HV 2.71–2.87, 2.77.

Distribution: This species previously was known only from the Holarctic Region. It is now known from three southern Chinese provinces (Fujian, Guizhou, and Taiwan) of Oriental China and one northern Chinese province (Neimenggu Autonomous Region) of Palaearctic China.

Remarks: The LRI (0.77–0.86, 0.82) and LRIII (0.80–0.86) of Chinese specimens are greater than the LRI (0.72) and LRIII (0.73) described by Fittkau (1962). The wing length of the Chinese specimens (1.99–2.45, 2.18 mm) is less than the wing length (4 mm) described by Fittkau (1962).

Tables

TABLE 1. Lengths (µm) and proportions of legs of N. nugax (Walker).

	fe	ti	ta1	ta2	ta3	ta4	ta5	LR
p1	975–1175, 1038	1175–1375, 1253	960–1150, 1040	440–550, 483	320–370, 337	210–250, 227	130–160, 143	0.77–0.86, 0.82
p2	1075–1225, 1130	1100–1275, 1155	650–770, 507	300–380, 330	220–260, 233	140–160, 150	100–125, 112	0.59–0.63, 0.61
p3	975–1100, 1015	1038–1375, 1198	920–1000, 960	410–410	1300–32 0	190–210	120–140	0.80–0.86