Drepanosticta annandalei, 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 : 412-413

9. Drepanosticta annandalei , sp. nov.

(Plate XXIV, fig. 12.)

One adult male, one teneral male and one very teneral female, from Mt. Harriet , 800 ft., S. Andamans. In deep jungle, at edge of stream, 3. XII. 23. coll. N. Annandale .

Male. Abdomen 32 mm. Hindwing 22 mm.

Head. Labium brown, labrum creamy white narrowly bordered with glossy black, rest of head matt black, except basal and penultimate segments of antennae which are white. Eyes dark olivaceous brown, paler below.

Prothorax dirty white with a large black lateral spot on each side.

Thorax dark blackish brown on dorsum, the middorsal carina and upper part of humeral suture paler, sides white with a diffuse longitudinal brown fascia traversing the sutures obliquely as far as posterior border of metepimeron.

Wings hyaline, rather falcate; 16 postnodal nervures in the forewing, 14 in the hind; pterostigma dark blackish brown; ac very oblique from before back, the anal bridge very oblique from behind forwards and meeting the underside of quadrilateral about its middle.

Legs white, the knees black, femora black on extensor surface, this spotted with white; posterior and middle tibiae with long hair-like spines gradually shortening towards distal ends of tibiae, anterior tibiae with similar spines on proximal half, but the distal ends furnished with a row of short, evenly sized, closely-set spines.

Abdomen white at sides, black on dorsum, the black not quite reaching base of segments but expanding apically to form thick rings; segment 8 with apical third and a fine dorsal stripe extending to the base black, 9 and 10 wholly black. Segments 7 to 10 shorten progressively.

Anal appendages of equal length, slightly longer than segment 10, the superior black, rather spatulate, curling inwards and downwards on themselves at about their middles, their apices nearly meeting. Inferior broad at base, tapering to a blunt point.

Female. Abdomen 25 mm. Hindwing 20 mm.

Colouring as for male but segment 8 is black in its apical half, 9 has the apical third black, 10 is all black. Anal appendages very minute, white.

Wings hyaline, postnodal nervures 14 to 16; pterostigma pale brown.

In the teneral male, the apices of all segments are ringed with white, the dorsal black band indicated by a mere clouding, segment 9 also has its basal half white and the appendages are of the same colour.

This species is distinguished from D. carmichaeli Laid , by its simple black and white colouring. As regards the Ceylon group, tropica , montana , digna and hilaris , I am of opinion that that they form a distinct group within the Legion Platysticta , probably having a generic value of their own in any case; they may be distinguished from the present species by the blue markings on segments 9 and 10, segment 9 in annandalei being marked with white, and 10 being wholly black.

From D. hilaris , from Burma, it may be distinguished by the totally different shape of the anal appendages.