Corynoneura enormis Fu, 2022

Fu, Yue, Fang, Xiang-Liang, Wang, Xin-Hua, Shen, Mi & Xiao, Yun-Li, 2022, Corynoneura Winnertz species from Hunan Province, Oriental China, delineated with morphological and 16 S rDNA data (Diptera, Chironomidae), ZooKeys 1082, pp. 87-102 : 87

Corynoneura enormis Fu sp. nov.

Figure 1

Type material.

Holotype, male (HNU: 17091206HJL), China: Hunan Province, Loudi City, Xinhua County, Xihe Town, Cushi Village, 27°51'45"N, 111°31'51"E, 315 m a. s. l., 29.Ⅶ.2016, sweep net, leg. Jingli Huang.

Etymology.

From Latin, Corynoneura enormis , immense, huge, vast, referring to lateral sternapodeme with a large attachment point.

Diagnosis.

The male imago is characterized by having an antenna with eight flagellomeres, AR 0.51; anterior margin of cibarial pump distinctly concave; hind tibia with hooked spur; superior volsella small rounded and undeveloped; inferior volsella narrow, with dented edge, along the inner margin of gonocoxite; phallapodeme apically curved, placed in lateral position of sternapodeme; sternapodeme curved into a U-shape, and lateral sternapodeme with large caudal attachment point.

Description.

Adult males (N = 1). Total length 0.92 mm. Wing length 0.53 mm. Total length/wing length ratio 1.74. Wing length/profemur length ratio 2.69.

Coloration. Head dark brown; thorax dark brown. Legs yellowish. Abdomen brown.

Head. Antenna with eight flagellomeres, AR 0.51, ultimate flagellomere 115 µm long, with many short apical sensilla chaetica (Fig. 1C ). Tentorium and cibarial pump as in Figure 1B , tentorium 110 µm long; 12 µm wide; Anterior margin of cibarial pump strongly concave. Clypeus with four setae.

Thorax. Five dorsocentral setae. Scutellum with two setae. One or two prealar setae.

Wing (Fig. 1A ). VR 3.0. Cu/wing length ratio 0.54; costa 120 µm long, with five setae; Cu 288 µm long; wing width/wing length ratio 0.45.

Legs. Fore trochanter with dorsal keel. Most of fore- and mid-legs lost. Spurs of hind tibia 25 µm and 10 µm long. Width of hind tibia at apex (a) 29 µm, width of hind tibia 1/3 from apex (d) 18 µm, elongation length (b) 34 µm, length of maximum thickening (c1) 48 µm, total length of thickening (c2) 72 µm; hind tibial ratios: a/d 1.61; b/d 1.89; c1/d 2.61; c2/d 4.00. Hind tibia expanded with comb of 17 setae and S-shaped spur (Fig. 1D ). Lengths and other proportions of legs given in Table 1 .

Hypopygium (Fig. 1E, F ). Tergite IX medially incurved. Superior volsella small, with rounded margin, anteromedially fused. Inferior volsella along inner margin of gonocoxite with many glandular setae. Phallapodeme scalpel-like, apical curved, 35 µm long, and joint with sternapodeme placed lateral. Transverse sternapodeme 20 µm wide, inverted U-shaped, with small oral projection, lateral sternapodeme with very large attachment point placed and directed caudally. Gonostylus curved tapering, 29 µm long; megaseta 5 µm long. HR 2.31; HV 3.17.

Remarks.

This species is similar to Corynoneura ascensa Fu & Sæther, 2012 and Corynoneura sesquipedalis Fu & Fang, 2018 by having a large attachment point on the lateral sternapodeme. The new species can be separated from C. ascensa by having antenna with 8 flagellomeres, narrow and undeveloped inferior volsella; and differs from C. sesquipedalis by having a narrow inferior volsella, transverse sternapodeme present and with an oral projection (broad inferior volsella, transverse sternapodeme V-shaped,without transverse part in C. sesquipedalis ). The sequence of 16S rDNA from this species is highly similar to Corynoneura tumula Fu & Fang, 2018, but there are distinct morphological differences between them: in C. enormis the antenna has 8 flagellomeres, AR 0.51; inferior volsella narrow, lateral sternapodeme with large caudal attachment point, while C. tumula has an antenna with 9 flagellomeres, AR 0.46; inferior volsella relatively broad, lateral sternapodeme with small caudal attachment point.

Figures

Figure 1. Corynoneura enormis sp. nov., male imago. A wing B tentorium and cibarial pump C apex of antenna D legs E hypopygium, dorsal view F hypopygium, ventral view.