Corynoneura aggeris Fu, 2020

Fu, Yue, Wang, Xin-Hua, Fang, Xiang-Liang, Xiao, Yun-Li, Fu, Jun & Lin, Xiao-Long, 2020, Corynoneura Winnertz (Diptera, Chironomidae, Orthocladiinae) from Zhejiang Province, China, Zootaxa 4890 (1), pp. 83-96 : 84-85

Corynoneura aggeris Fu , sp. n.

Fig. 1

Type material. Holotype male (NKU: A13I50), CHINA: Zhejiang Province, Hangzhou City, Changhua County, Qingliangfeng National Nature Reserve , 121°9′53″E, 30°17′49″N, a.s.l. 1100–1400 m, 12.V–20.VI.2012, malaise trap, leg. Rui Guo.

Etymology. From Latin, aggeris , heap, mound, referring to transverse sternapodeme curved between U- and V-shaped, peak like a small mound.

Diagnostic characters. The male imago is characterized by having an antenna with eight flagellomeres, AR 0.42; superior volsella small triangular, and anteromedially fused; inferior volsella narrowed, and placed caudally of gonocoxite; transverse sternapodeme narrow and without oral projection; the attachment point placed lateral sternapodeme is very small.

Description. Adult male (n = 1).

Total length 0.97 mm. Wing length 0.60mm. Total length/wing length 1.61. Wing length/profemur length 3.02.

Coloration. Head and thorax dark brown. Legs pale yellow. Abdomen yellow brown.

Head. Antenna with eight flagellomeres, AR 0.42. Ultimate flagellomere 95 µm long, slightly expanded apically, with ca. ten apical sensilla chaetica ( Fig. 1B ). Tentorium 113 µm long; 15 µm wide. Length of palpomeres (in µm): 15; 13; 15; 23; 45. Palpomere 5/3 ratio: 3.0.

Thorax. Dorsocentrals 4. Scutellum with 2 setae.

Wing ( Fig. 1A ). VR 3.2. Cu/wing length 0.60; C 160 µm long; Cu 360 µm long; wing width/wing length: 0.48. Costa with 8 setae.

Legs. Fore trochanter with dorsal keel. Spurs of fore tibia 23 µm long, of mid tibia 10 µm long and 8 µm long, and spurs of hind tibia 38 µm long and 12 µm long. Width at apex of fore tibia 20 µm, of mid tibia 15 µm, of hind tibia (a) 40 µm. Width of hind tibia 1/3 from apex (d) 25 µm, elongation length (b) 30 µm, length of maximum thickening (c 1) 55 µm, total length of thickening (c 2) 80 µm; a/d 1.4; b/d 1.2; c 1 /d 2.2; c 2 /d 3.2. Hind tibia expanded, with comb of 16 setae, one seta near spur strongly S-shaped ( Fig. 1C ). Lengths and proportions of legs as in Table 1.

Hypopygium ( Fig. 1 D-E). Tergite IX and laterosternite IX without long seta. Tergite IX medially incurved, and pair of low caudal mounds with many setae on each side. Superior volsella undeveloped, and anteromedially fused. Inferior volsella with many glandular setae, along the inner margin of gonocoxite and placed caudally. Phallapodeme scalpel-like, apex slightly curved, 32 µm long, without obvious projection, and join with sternapodeme placed caudally. Transverse sternapodeme very narrow, curved between U- and V-shaped. Lateral sternapodeme with small attachment point placed and directed caudally. Gonostylus straight, 25 µm long; megaseta 2 µm long. HR 2.32; HV 3.88.

Remarks. This species is similar to Corynoneura makarchenkorum Krasheninnikov, 2012 by having the same shape of the transverse sternapodeme and phallapodeme, but can be separated from the latter by the antenna with eight flagellomeres, AR 0.42; gonostylus straight in C. aggeris sp. n., while C. makarchenkorum has the antenna with 12 flagellomeres, AR 0.92–1.00, and apically curved gonostylus.

Figures

FIGURE 1. Corynoneura aggeris sp. n., male imago. A. wing; B. antenna; C. hind tibial apex; D. hypopygium, dorsal view; E. hypopygium, ventral view.