Corynoneura lateralis 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 : 86

Corynoneura lateralis Fu , sp. n.

Fig. 2

Type material. Holotype male (NKU: L7A29), CHINA: Zhejiang Province, Lishui City, Longquan County, Fengyangshan Mountains , 119°13′31″E, 27°56′23″N, a.s.l. 1200–1700 m, 25.VII.2012, sweep net, leg. Xiao-Long Lin. Paratypes: 3 males (NKU: A13G12, A13G23, A13G28), Zhejiang Province, Hangzhou City, Lin’an County, Tianmushan Mountains , a.s.l. 970–1100 m, 24.VII.2011, sweep net, leg. Xiao-Long Lin. 1 male (NKU: G5A41), Zhejiang Province, Jinhua City, Pan’an County, Dapanshan Mountains , 120°31′30″E, 28°47′30″N, a.s.l. 800 m, 17–21.VII.2012, light trap, leg. Xiao-Long Lin. 1 male (NKU: L7A9), Zhejiang Province, Lishui City, Baishanzu Mountains , 119°11′39″E, 27°45′20″N, a.s.l. 1450 m, 25.VII.2012, light trap, leg. Xiao-Long Lin.

Etymology. From Latin, lateralis , of the side, referring to the phallapodeme join with sternapodeme placed laterally.

Diagnostic characters. The male imago is characterized by having an antenna with eight or nine flagellomeres, AR 0.4–0.5; anterior margin of cibarial pump distinctly concave; hind tibia with hooked spur; superior volsella developed, anteromedially fused; inferior volsella with dented edge, placed caudally on gonocoxite; phallapodeme almost straight, placed in a lateral position to the sternapodeme; sternapodeme curved into U-shape, and lateral sternapodeme with caudal attachment point.

Description. Adult males (n = 6).

Total length 0.81–1.02, 0.94 mm. Wing length 0.60 mm. Total length/wing length 1.48–1.69,1.57. Wing length/ profemur length 2.68–3.0, 2.86.

Coloration. Head dark brown, with black eyes. Thorax dark brown. Legs yellowish. Abdomen yellow brown.

Head. Antenna with eight or nine flagellomeres; when eight flagellomeres: AR 0.50–0.51, ultimate flagellomere 118–125, 121 µm long; when nine flagellomeres: AR 0.41–0.44, ultimate flagellomere 88–113, 100 µm long, ultimate flagellomere slightly expanded apically, with many short apical sensilla chaetica ( Fig. 2D ). Tentorium and cibarial pump as in Fig. 2B , tentorium 105–138, 120 µm long; 13–18, 15 µm wide; stipes 45–63, 50 µm long, 3 µm wide. Anterior margin of cibarial pump distinctly concave. Clypeus with 10 setae. Length of palpomeres (in µm): 8–10, 9; 10–15, 13; 15–20, 18; 20–23, 21; 38–45, 42. Palpomere 5/3 ratio: 2.0–2.9, 2.5.

Thorax. Dorsocentrals 5–7, 6. Scutellum with 2 setae. Prealars 2 or 3.

Wing ( Fig. 2A ). VR 5.4. Cu/wing length 0.45–0.55; C 149–155, 150 µm long; Cu 270 µm long; wing width/ wing length: 0.44–048, 0.46. Brachiolum with 1 seta, costa with five or six setae.

Legs. Fore trochanter with dorsal keel. Spur of fore tibia 18–25, 20 µm long, spurs of mid tibia 10–18, 15 and 12–18, 15 µm long, and spurs of hind tibia 25–33, 30 µm long and 8–13, 10 µm long. Width at apex of fore tibia 15–18, 16 µm, of mid tibia 15–18, 16 µm, of hind tibia (a) 15–20, 18 µm. Width of hind tibia 1 / 3 from apex (d) 15–20, 18 µm, elongation length (b) 30–43, 35 µm, length of maximum thickening (c 1) 55–75, 65 µm, total length of thickening (c 2) 85–125, 95 µm; a/d 1.39–2.2, 1.64; b/d 1.65–2.87, 2.72; c 1 /d 3.06–3.87, 3.50; c 2 /d 4.72–6.25, 5.56. Hind tibia expanded, with comb of 15–20, 18 setae, with hooked spur ( Fig. 2C ). Lengths and proportions of legs as in Table 2.

Hypopygium ( Fig. 2 E–F). Tergite IX medially distinctly incurved. Superior volsella with rounded margin, anteromedially fused. Inferior volsella with many glandular setae and dented margin, along the inner margin of gonocoxite and placed caudally. Phallapodeme short and scalpel-like, almost straight, 25–33 µm long, and joint with sternapodeme placed lateral. Transverse sternapodeme 17–23, 20 µm wide, with oral projection, lateral sternapodeme with attachment point placed and directed caudally. Gonostylus curved tapering, 20–27 µm long; megaseta 5 µm long. HR 2.39–3.25, 2.67; HV 3.27–4.96, 3.91.

Remarks. This species is closely related to Corynoneura sundukovi Makarchenko et Makarchenko, 2010 by having similar inferior volsella and inverted U-shaped sternapodeme. The new species can be separated from the latter by having the antenna with eight or nine flagellomeres, short and straight phallapodeme and joint with sternapodeme placed lateral, while C. sundukovi has antenna with 12 flagellomeres, phallapodeme low and curverd, joint with sternapodeme placed caudally. The new species is also similar to Corynoneura inefligiata Fu, Saether et Wang, 2009 by having same shaped sternapodeme and phallapodeme, but differs from the latter by the antenna with ten flagellomeres, inferior volsella large and broad in C. inefligiata .

Figures

FIGURE 2. Corynoneura lateralis sp. n., male imago. A. wing; B. tentorium and cibarial pump; C. hind tibial apex; D. antenna; E. hypopygium, dorsal view; F. hypopygium, ventral view.