Pseudagrion coriaceum Selys, 1876

Pseudagrion coriaceum Selys, 1876 View in CoL

Figures: 17–19 (lectotype ♂, labels); 81 (head ♂); 98 (pterothorax ♂); 115a, b (abdomen ♂); 132a–c (caudal appendages ♂); 152–153 (field photos ♂).

Pseudagrion coriaceum View in CoL : Selys (1876): 513 (description ♂, Ambon);— Ris (1915b): 97 –98, Fig. 19 (♂ appendages; key; Seram);— Campion (1921): 263 ( Ambon);— Ris (1929): 146 (description ♀; Ambon).

Examined specimens from the type series (2♂♂)

♂ lectotype, 1859, Amboina [ Ambon, Indonesia], Dr Doleschal leg., NHMW ( Figs 17–19) ;— 1♂ paralectotype, 1859, Amboina [ Ambon, Indonesia], Dr Doleschal leg., NHMW .

Lectotype designation by St. Quentin (1970). Both males lack the last segments of the abdomen, including the caudal appendages.

Other specimens examined (6♂♂, 3♀♀)

Indonesia, Ambon Island: 1♀, without particular locality, IRSNB ;— 3♂♂, 23.iv.1941, Soengai, Waitoemoe, Mains z lasoen, RMNH , no. 1519109;— 1♀, 27.vii.1948, without particular locality, M.A. Lieftinck leg., RMNH , no. 1519104;— 1♀, 12.x.1949, without particular locality, M.A. Lieftinck leg., RMNH , no. 1658923.

Indonesia, Seram Island: 1♂, 18.ix.1912, without particular locality, Elgner leg., SMF , no. 13924;— 1♂, 21.xi.1941, Wahai , van der Harre leg., RMNH , no. 1519260;— 1♂, 30.xi.1996, stream 500 m NE of Logging Base Camp, 1.5 km SW Roho village , 31 km SW of Wahai, M. Bedjanič leg., MB .

Characterization of male

Head ( Figs 17, 81): Labrum, clypeus, antefrons and postfrons yellow; postfrons distinctly separated from black vertex around level of lateral ocelli; postocular spots large, reddish-brown, but they may be darkened and hardly visible; reddish occipital bar, but may be darkened and hardly visible; rear of head black, but broadly pale along the eye margins; eyes brownish, in life anteriorly yellow, continuing the yellow of the frons; base and scape antennae yellow, following segments brownish.

Thorax ( Figs 17, 18, 98): Anterior lobe of pronotum red, this colour extending towards middle lobe in posterior centre; middle pronotal lobe otherwise black, with a centrally divided red patch in the middle, and on each side a large red patch dorsolaterally, these may fuse laterally with red of anterior lobe; propleuron black above, broadly yellowish-red below and to rear; posterior lobe of pronotum red; apical edge of posterior lobe almost convex. Pterothorax red with black middorsal stripe; a black humeral stripe of same width; interpleural suture with a black stripe, and a dark dot anteriorly; metapleural suture with a black stripe, widened posteriorly; ventrally pale. Legs orange-reddish; outer side of femora with a blackish stripe narrowing to proximal; along spines of tibiae, and the waists blackish; spines black.

Abdomen ( Figs 115a, b): S1 red, dorsally with black patch covering the anterior two-thirds of the segment, the patch may be divided in half by a red middorsal line; S2 red, but along posterior carina black; with blackish mushroom-like marking dorsally at posterior quarter, this marking may extend as a black middorsal stripe towards the segment base; S3–8 dorsally black, laterally pale yellow-red; S9 red, dorsally with a black middorsal stripe and with at least the posterior third to half black, the black margin may be serrated, but dorsum of S9 may likewise be completely black; S10 red, dorsally with a black “x”-like marking, variable in exact shape.

Caudal appendages ( Figs 132a–c): Cercus laterally dark, slightly shorter than S10; in lateral view cercus simple, subtriangular, inter-lobe notch not visible; in dorsal view apex of superior lobe rounded and deep inter-lobe notch visible; inferior lobe bulging smoothly inwards; paraproct pale yellow-ochre, as long as two-third of the cercus; in lateral view subtriangular and tapered with rounded apex; in dorsal view broadly rounded, concave bowl-like, its medial edge blackish tubercular.

Characterization of female

Head: Labrum, and anteclypeus yellow-ochre; postclypeus blackish; antefrons and postfrons yellow-ochre, antefrons with blackish patch in centre and a black mid stripe towards postclypeus; vertex black from about level of lateral ocelli; postocular spots orange-ochre; occipital bar orange-ochre; rear of head black, but broadly pale along the eye margins; base and scape of antennae yellow-ochre, following segments brownish.

Thorax: Anterior lobe of pronotum orange-ochre, its anterior margin black; middle pronotal lobe and posterior lobe as in male but orange-ochre; posterior lobe bearing two horns directed towards head, almost reaching the centre of the middle lobe; apical edge of posterior lobe almost convex. Pterothorax and legs as in male but orange-ochre.

Abdomen: S1 orange, with a blackish dorsal marking at anterior two-third; S2 red, with a black middorsal stripe, widened to lateral at posterior quarter; S3–10 dorsally black, laterally orange-ochre; on S9–10 the orange-ochre expanded dorsally in centre, with the anterior and posterior margin, as well as the dorsum of each segment black. Cercus blackish, as long as half of S10; paraproct darkish ochre; in lateral view rounded; ovipositor pale yellowish-ochre, its apex not reaching to posterior end of S10; two yellow-brownish styles reaching beyond S10; inferior edge of ovipositor bearing several very small teeth.

Wings of both sexes with 13.5–15.5 px in forewing, and 12.0–13.5 px in hindwing.

Measurements of both sexes (mm): Total length (with appendages) 43.2–46.6; abdomen length (without appendages) 35.2–38.5; hindwing 24.0–26.7; forewing 25.4–28.0; Pt in forewing 0.8–1.0; male cercus 0.5.

Diagnosis

Pseudagrion coriaceum is currently the only known species of the Pseudagrion red-group which occurs on Ambon and Seram. Males can be separated from all congeners by the distinct morphology of the cercus ( Figs 132a– c), being subtriangularly tapered with inferior lobe and inter-lobe notch not visible in lateral view. The only species with a superficially similar morphology of the male cercus is P. halmaherae ( Figs 137a–c), but in this species the cercus is less tapered in lateral view and an inter-lobe notch is situated subapically at the lower margin. The obvious pterothorax pattern of P. coriaceum ( Figs 17, 18, 98, 152, 153) separates this species from several congeners as well.

Distribution

This species is restricted to Ambon and Seram ( Fig. 3).