Idionyx selysi Fraser, 1926

Zhang, Haomiao & Tong, Xiaoli, 2010, Descriptions of the final instar larvae of three Chinese Idionyx species (Odonata: Anisoptera: Corduliidae), Zootaxa 2716, pp. 53-63 : 56

Idionyx selysi Fraser, 1926

Figures 12 –20, 32–33, 36– 37

Material examined. 1 ɗ and its exuviae, 01.IX. 2009, Mengla (21 ° 37 ʹ0 4 ʺN, 101 ° 35 ʹ0 3 ʺE), Xishuangbanna, Yunnan Province, China, Haomiao Zhang leg.; 1 final stage larva, same data but 03.IX. 2009; 1 Ψ and its exuviae, same data, emerged on 30.IX. 2009.

Ground color of body yellowish brown with dark brown maculation ( Fig. 36). Small sized with total body length 14.0 mm, head width maximum 4.0 mm; length of hind femur 4.5 mm.

Head—Yellowish brown without conspicuous maculation. Eyes large, knob-like; antefrons and hind margin of eyes with short setae; upper surface of frontal plate concave; mandibles similar to I. carinata ( Figs 32–33) and with same mandibular formula as in I. carinata , but apices of incisors 1, 3 and 4 pointed; clypeus and labrum entirely concealed beneath broad labial mask ( Fig. 12); postmentum extending about halfway between mid and hind coxae; premental setae: 5 + 4 / 4 + 5; apex of prementum not bifid, with robust setae, and its distal margin lacking conspicuous crenulations, with 11–13 spiniform setae on each side; palpal lobes strongly developed ( Fig. 13), their inner margin with 8 teeth, all with spiniform marginal setae, the outermost one triangle-shaped, others rounded, dark brown; outer margin of lobes with a row of setae; palpal setae: 5 / 5; moveable hook short and pointed at apex. Antennae filiform, 7 -segmented ( Fig. 15). Length of each antennal segments (mm): 0.16: 0.28: 0.25: 0.17: 0.17: 0.17: 0.25.

Thorax—Thorax almost as broad as the transverse diameter of head. Pronotum strongly developed ( Fig. 14) with 3 transverse depressions; synthorax fringed with long setae; wing pads strongly divergent extending to middle of S 7. Legs long and slender, femora and tibiae each with 4–5 long, stout, prostrate, clavate setae; front femora yellowish with a dark brown stripe subdistally; middle and hind femora yellowish with two dark brown stripes submedially; tibiae yellowish with a dark brown marking basely.

Abdomen—Short and oval, depressed, ground color yellowish brown, all segments fringed laterally with long hair-like setae; S 4 & 10 with a pair of small dark brown spots dorsally, S 5–9 with two pairs of dark brown spots dorsally, S 5–8 with a pair of central brown spots ventrally; dorsal hooks absent; large lateral spines present only on S 8 & 9; S 10 short; anal appendages short, epiproct and paraprocts straight, triangular, cerci subequal to paraprocts in length.

Distribution. China (Yunnan), Laos, Burma, and Thailand