Pseudagrion andamanicum, F.C. Fraser, 1924

F. C. Fraser, 1924, Report on a collection of dragonflies (Odonata) from the Andaman Islands., Records of the Indian Museum 26, pp. 409-413 : 411-412

7. Pseudagrion andamanicum , sp. nov.

(Plate XXIV

figs. 6—8, 10, 11.)

One pair from the same locality as last .

Male. Abdomen 25 mm. Hindwing 17 mm.

Head. Labium white, rest of head azure blue marked with black, a small spot in front and one on either side of middle ocellus, a narrow ragged transverse stripe at level of posterior ocellus, and finally a narrow black bordering to the hinder part of the large postocular spots. Eyes bluish above changing to greenish yellow beneath and capped with a diffuse cloud of brown.

Prothorax blue with the usual Pseudagrion black markings.

Thorax azure blue, marked with black as follows:—a narrow middorsal stripe and somewhat narrower humeral ones, which latter do not quite reach the upper margin of thorax, a small black spot on middle of first lateral suture and a smaller one on upper part of postero-lateral suture.

Legs pale blue, all femora black on extensor surfaces.

Wings faintly enfumed, pterostigma dark brown; 11 to 12 postnodal nervures to forewings, 8 to 9 in the hind.

Abdomen blue marked with black as follows:—a small spot on dorsum of segment 1 extending nearly to apical margin, 2 with a narrow apical ring connected by a narrow neck to a rectangular dorsal spot, the basal half of the middorsal carina between this spot and base of segment finely black, segments 3 to 6 with middorsal longitudinal stripes expanding apically and then contracting again to join narrow apical rings, 7 nearly all black, 8 and 9 blue with moderately broad apical black rings, that on segment 8 double the width of the one on 9,10 black dorsally.

Anal appendages. Superior as long as segment 10, black, blue within, deeply bifid at apices. Inferior shorter, sloping up towards the superiors, broad at base, tapering, dirty white in colour.

Female. Abdomen 27 mm. Hindwing 20 mm.

Head somewhat similar to that of male but the transverse stripe absent, 3 minute black spots at base of labrum and two large diffuse spots between the postocular spots. Ground colour bluish green in front, greenish above.

Prothorax greenish blue, marked similarly to the male.

Thorax. Ground colour of one female azure blue, of the other greenish, with diffuse golden brown middorsal and humeral fasciae, a small black point at upper end of humeral suture and another at upper end of 2nd lateral, the median point of the first lateral suture smaller than in the male.

Wings hyaline, 11 postnodal nervures in forewings, 9 in the hind; pterostigma pale brown.

Legs pale bluish green with black spines and a black stripe on extensor surfaces of femora.

Abdomen blue in one female, bluish green in the other, black markings similar to those of male. In one female, the black spot on dorsum of segment 2 is very restricted and diamond-shaped, the carina is, however, finely black throughout its length and a golden halo surrounds the marking, segment 8 broadly black with a narrow basal blue ring, 9 has a baso-dorsal black spot connected, or narrowly interrupted by the blue, to a narrow apical linear spot. Segment 10 wholly blue.

Anal appendages dirty blue, very small, conical.

This species is related to the microcephalum group.