Idionyx carinata 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 : 54-56

Idionyx carinata Fraser, 1926

Figures 1–11 , 30–31 , 40–41

Material examined. 2 final stage larvae, 29.IX.2008, The Chebaling National Nature Reserve (24°42ʹ11ʺN, 114°11ʹ13ʺE), Guangdong Province, China, Haomiao Zhang leg.; 1 ɗ and its exuviae, same data, emerged 15.III.2009; 1 Ψ, 24.V.2009, The Nanling National Nature Reserve (24°55ʹ42ʺN, 113°01ʹ0 2ʺE), Guangdong Province, China, Haomiao Zhang leg.

Ground color of body brown with dark brown maculation ( Fig. 40 ). Small sized with body length 17.0 mm, head width maximum 5.0 mm; length of hind femur 5.0 mm.

Head—Brown with black maculation. Eyes large, knob-like; upper surface of frontal plate concave; mandibles

as in Figs 30–31 and mandibular formula: molar crest absent; a> b, present on both right and left at position of molar crest; incisor teeth rounded, 4> 1> 3> 2, 2 not well developed; additional tooth y on right mandible; clypeus and labrum entirely concealed beneath labium mask; labrum brown with front margin black; anteclypeus brown with a pair of semicircular black spots; postclypeus, frons and ocellar triangle brown without conspicuous spots; antefrons with short setae; labial mask broad ( Fig. 1 ) with mental setae of prementum: 5+5 / 5+5; apex of prementum not bifid, with robust setae, and its distal margin lacking conspicuous crenulations, and with 20 spiniform setae on each side; palpal lobes strongly developed ( Fig. 2 ), their inner margin with 8 teeth, the outermost triangular, others rounded, and all with spiniform marginal setae; outer margin of lobes with a row of setae; palpal setae: 5 / 5; moveable hook short and only slightly curved. Antennae filiform, 7-segmented ( Fig. 3 ). Length of each antennal segments (mm): 0.22: 0.27: 0.28: 0.22: 0.22: 0.22: 0.22.

Thorax—Thorax almost as broad as the transverse diameter of head. Pronotum strongly developed ( Fig. 4 ) with 3 transverse depressions; synthorax fringed with long setae; wing pads strongly divergent, almost black, with yellow spots on the fore margin, reaching posterior margin of S7. Legs long and slender, femora and tibiae each with 4–6 long, stout, claviform setae dorsally; femora yellowish with two dark brown stripes submedially; tibiae yellowish with dark brown maculation basely.

Abdomen—Short and squat with ground color brown, fringed with long hair-like setae laterally; S3 & S4 with a pair of irregular black spots dorsally, S5–10 with two pairs of irregular black spots dorsally, S5–9 with a rounded black spot medially and ventrally; dorsal hooks absent; small lateral spines present only on S8 & S9; S10 short; anal appendages short, epiproct and paraprocts straight, triangular, cerci subequal to paraprocts in length.

Distribution. China (Guizhou, Guangdong, Guangxi, Fujian, Zhejiang, and Hunan) and Laos.

Figures

FIGURES 1 – 4. Larva of Idionyx carinata Fraser: (1) labial mask, dorsal view; (2) right palpal lobe, ventral view; (3) antenna; (4) pronotum, dorsal view.

FIGURES 5 – 11. Idionyx carinata Fraser: (5) head, male, frontal view; (6) head, female, frontal view; (7) head, female, lateral view; (8) caudal appendages, male, dorsal view; (9) caudal appendages, male, lateral view; (10) thorax and abdomen, male, lateral view; (11) thorax and abdomen, female, lateral view.

FIGURES 30 – 35. Inner surface of mandibles of Idionyx larvae: 30 – 31. Idionyx carinata Fraser: (30) right mandible; (31) left mandible; 32 – 33. I. selysi Fraser: (32) right mandible; (33) left mandible; 34 – 35. I. victor Hämäläinen: (34) right mandible; (35) left mandible.

FIGURES 36 – 41. 36 – 37. Idionyx selysi Fraser: (36) final instar larva; (37) male adult; 38 – 39. I. victor Hämäläinen: (38) final instar larva; (39) male adult; 40 – 41. I. carinata Fraser: (40) final instar larva; (41) male adult.