Chlorogomphus yokoii Karube, 1995

Zhang, Haomiao & Tong, Xiaoli, 2013, Descriptions of the final instar larvae of seven Chinese Chlorogomphidae species, with taxonomic notes on adults (Odonata: Anisoptera), Zootaxa 3620 (2), pp. 223-244 : 236-239

Chlorogomphus yokoii Karube, 1995

Figures 36–44 , 55–58 .

Chlorogomphus yokoii Karube, 1995b: 50 -51, figs. 12–19. Type Locality: Nan, N. Thailand.

Material examined. 13 and its exuvia, 01.IX.2009, Mengla (21°29ʹ43ʺN, 101°31ʹ59ʺE), Xishuangbanna, S. Yunnan Province, China, Haomiao Zhang leg., emerged on 01.V.2010;1Ƥ and its exuvia, same date, emerged on 03.V.2010; 2 final instar larvae, same data.

Medium-sized chlorogomphid larva with variable ground color and maculation.

Head Brownish yellow, pale brown or reddish brown. Postclypeus with brown spots centrally. Frontal shelf as in Fig. 40 , mandibles as in Figs. 36–37 .

Mandibular formula:

Left mandible with 5 rounded molar crest, a complanate, b rounded, a> b; teeth of the incisors pointed, 4>3>2>1>2’, 2’ located in the cleft between 1 and 2; right mandible without molar crest, a and b pointed, a> b; teeth of the incisors pointed, 4>1>3>2, additional tooth y present on the right mandible; labial mask as in Fig. 38 . Prementum with row of 6 long outer setae and 3–5 smaller inner setae on each side; distal process as in Fig. 39 ; bifid lobes of the distal process angled, each lobe bent slightly outwards.

Thorax Yellow, pale brown or reddish brown with long hair-like setae. Pronotum strongly developed with brown stripes, sides of synthorax slightly tinted with black; wing pads strongly divergent, color identical to synthorax, reaching hind margin of S4; femora and tibiae with brown stripes submedially.

Abdomen S1–3 with pair of small brown spots centrally; S4–6 with a pair of oval brown spots centrally and pair of crescent-shaped brown spots laterally; S7–9 with pair of oval brown spots centrally and pair of crescentshaped brown spots laterally, less developed than those present on S4–6; lower side of S10 black.

Measurements (mm). Total length 36.0–36.5, head width 8.0–8.5, hind wing length 9.0, width 3.5, hind femur 6.5, prementum length 7.0, width 8.0.

Distribution. China (Yunnan) and north Thailand.

Remarks. Described from Thailand and now known to occur in Yunnan, China. The male adult reared from a larva is illustrated in Figs. 41–44 . This is the first arooni -group species from mainland China, easily distinguished by the male caudal appendages. The larvae were found in some open streams around altitude 350 m. Larvae are very variable in ground color, and at least four forms were collected: 1) largely yellow with brown head and black abdominal spots; 2) predominantly orange with brown spots; 3) entirely reddish brown without remarkable spots; 4) largely yellowish brown with dark brown head and black abdominal spots. The larvae were active when disturbed. The larva is similar to that of Chlorogomphus shanicus in possessing 6 long premental setae but can be distinguished from the latter by the following characters: 1) color of sides of synthorax is identical to the ground color of body or only slightly darkened, yellowish brown or reddish brown (sides of synthorax black in C. shanicus ; 2) wing pads identical in color to body, yellowish brown or reddish brown (black wing pads in C.

shanicus ); 3) S6 without dorsal black spots centrally (large dorsal black spots, about 1/3 width of S6, in C. shanicus ); 4) body size and head width smaller than C. shanicus ; 5) left mandible with 5 molar crest (6 in C. shanicus ).

Figures

FIGURES 36 – 40. Larva of Chlorogomphus yokoii: (36) right mandible; (37) left mandible; (38) prementum, dorsal view; (39) bifid branches of frontal margin of prementum; (40) frontal shelf, dorsal view.

FIGURES 41 – 44. Male adult of Chlorogomphus yokoii: (41) male, dorsal view; (42) head, lateral view; (43) same, frontal view; (44) thorax and basal abdominal segments, lateral view.

FIGURES 54 – 59. Larvae of Chlorogomphidae: (54) Chlorogomphus usudai; (55 – 58) Chlorogomphus yokoii; (59) Chloropetalia soarer.