Parameletus arcuatus sp. nov.

(Figs. 9–15)

Holotype. RUSSIA. Khabarovskiy Kray: Bikin River, 50 m lower motor-car bridge, line Vladivostok-Khabarovsk, 16.VI 2005, T Tiunova, 1 male imago.

Paratypes. Together with holotype, 26 male imagines. Primorskiy Kray, Bolshaya Ussurca River, 2 km lower Zvenigorodka village, 8.VI 2004, T Tiunova, 1 male imago.

Description. Male imago (in alcohol). Dimensions: length (mm): body 13.0 – 15.7; fore wings 11.8 – 13.3; cerci 20.5 – 22.5. Total color of living imago dark brown. Head: upper portion of eyes light brown, lower portion black. Thorax: Mesonotum light brown tinged with grayish; dorsal arc of prealar bridge dark brown, posterior scutal protuberance brown (Fig. 15); mesosternum from dark brown to black. Fore legs brow; middle and hind legs light brown, tinged with grayish. Length (mm) of foreleg segments: femora 2.8– 3.5; tibiae 2.3–2.5; tarsal segments 1.5–1.7, 1.6–1.8, 1.7–1.9, 0.9–1.2. Wings hyaline, tinged with brownish; all veins brown (Figs. 12–13); pterostigma dead. The relation of length to the maximal width makes for fore wing—2.53, hind wing—1.60. Abdomen: terga 2–7 translucent, brown; terga 1 from dark brown to black; terga 4–7 with pair of dark brown spots like stroke in anterior margin; terga 7–8 opaque; lateral part of all terga darkened with brown. Sterna 2–6 translucent, brown or dark brown with pair of small light spots in middle part; sterna 7–9 from dark brown to black. Gonostyli and penis brown or dark brown. Posterior margin of styliger with a broad rectangular projection in middle part (Fig. 14). External penis lobes wide with rounded apices; inner penis lobes narrow, curved in base, with furcated apices, reaching apices of external lobes (Figs. 9–10). Ventral processes dark brown, pointed, reach to 2/3 of length of external lobes (Figs. 10–11). Cerci brown, base dark brown.

Female imago and nymph: Unknown.

Etymology. The epitet arcuatus is connected with form of inner penis lobes (Fig. 9).

Distribution and biology. Sought of Russian Far East: Khabarovskiy Kray and Primorskiy Kray (Fig. 8). The imagines were collected in grass and on leaves of trees which grow near the water together with Parameletus ensiformis sp. nov.

Discussion. Parameletus arcuatus is similar to P. chelifer; however male imago can be distinguished from that of P. chelifer by the structure of penis (Figs. 9–10) and form of posterior margin of styliger (Fig. 14).