Demicryptochironomus (Irmakia) neglectus Reiss 1988

Yan, Chuncai, Tang, Hongqu & Wang, Xinhua, 2005, Demicryptochironomus Lenz from China (Diptera: Chironomidae), Zootaxa 910, pp. 1-31 : 20-22

Demicryptochironomus (Irmakia) neglectus Reiss 1988 ( Figs. 8 A–C)

Demicryptochironomus (Irmakia) neglectus Reiss 1988: 7 ; Zorina 2004: 234

Material examined: 1 male: Xinjiang Autonomous Region, Haba River, Baihualin Natural Conservation. 15. VII. 2002, sweep net, H. Tang. (BDN no. 21802).

Diagnostic characters: The species can be distinguished from other species by having Y­shaped anal tergite bands, a slim conical anal point with a basal crest, and a gonostylus with the inner margin strongly concave in the middle. In the Chinese specimen, the anal tergite bands are Y­shaped, but not joined in the middle.

Male imago (n = 1)

Total length 3.13 mm. Wing length 1.68 mm. Total length/wing length 1.86. Wing length/ length of profemur 2.21.

Coloration: Thorax brown. Abdomen with tergites I–V yellowish brown and tergites VI–VIII brown, hypopygium dark brown. Apex of femora, tibia, and tarsi of fore legs brown, the rest yellowish green. Femora and tibiae of mid and hind legs yellowish green, tibia dark brown towards tarsus IV.

Head: AR 1.81, Ultimate flagellomere 580 µm long. Frontal tubercles small, rounded, 3 µm in diameter. Temporal 9 setae, including 3 inner verticals, 6 outer verticals. Clypeus with 7 setae. Tentorium 118 µm long, 23 µm wide. Palpomere lengths (in µm): 28, 38, 142, 145, 205.

Thorax: Antepronotals 2, dorsocentrals 8, acrostichals 5, prealars 4. Scutellum with 12 setae.

Wing ( Fig. 8 A): VR 1.10, R with 13 setae, R1 with 12 setae, R4+5 with 10 setae. Brachiolum with 2 setae. Squama with 6 setae. Anal lobe well developed.

Legs: Spur of middle tibia 15 µm; 20 µm long, comb with 30 teeth, 8–10 µm long; Spur of hind tibia 20 µm; 26 µm long, comb with 40 teeth, 8–10 µm long. Tarsus 1 of mid legs with sensilla chaetica 1. Lengths (in µm) and proportions of legs:

Hypopygium ( Figs. 8 B, C): Anal tergite bands Y­shaped, but not medially joined. Anal point 87 µm long, 18 µm wide at base, 10 µm wide at apex, slim conical, bluntly rounded distally, basally with crest. Tergite IX with 12 setae. Laterosternite IX with 7 setae. Phallapodeme 80 µm long. Transverse sternapodeme 35 µm long. Superior volsella cylindrical, nearly straight, with 2 apical setae. Gonocoxite 83 µm long, inner margins forming blunt median angle, with 3 setae. Gonostylus 208 µm long. Distal part of gonostylus nearly parallel sided, strongly curved, apically rounded. HR 0.40; HV 1.50.

Distribution: The species has a distribution in the Palaearctic region. This record is the first for China.

Figures

FIGURE 8. Demicryptochironomus (Irmakia) neglectus Reiss 1988. A. Wing. B. Dorsal view of hypopygium. C. Ventral view of hypopygium.