Amphicnemis billitonis, M.A. Lieftinck, 1940

M. A. Lieftinck, 1940, Descriptions and records of South-East Asiatic Odonata (II), Treubia 17 (4), pp. 337-392 : 374

Amphicnemis billitonis , sp. n. ( pl. 15 fig. 4 , pl. 16 fig. l ).

Material studied: — 6 ♂ (ad.), 15 ♀ (8 juv., red, 7 ad., blue), Billiton I. (west), Tjeroetjoek and Goenoeng Aoer, Sept. 21 - 27, Oct. 3, Nov. 19, and Dec. 24, 1935, April 7, 1936, F. J. Kuiper leg., in the Buitenzorg Museum. Holotype ♂ and allotype ♀: Tjeroetjoek, Dec. 24, 1935 .

Obviously most closely allied to wallacei , Selys.

Male (ad.). — Differs from wallacei in the following respects:

All but the middle of the anterior margin of labrum- shining black. Pale fascia in front of frons broadly interrupted on middle. Metallic-green colour on dorsum of synthorax more extensive laterally and ceasing at the spiracle ( wallacei : slightly before level of spiracle). Pterostigma blackish-brown or black, without yellow margin in adult specimens ( wallacei : greyish-brown with distinct yellow margin in both pairs of wings). The stru-ctural differences are given in the key to the species.

Anal appendages white, or wax-yellow in the younger male, pale brown tipped with purplish-black in matured individuals ( pl. 16 fig. 1 ).

Female. - The red and blue-green colour-phases are inseparable from those of wallacei and gracilis , described before. The tip of the prothoracic spine is yellowish or almost hyaline in adult specimens.

Figures

Pl . 15 . — Structural characters of Malaysian species of Amphicnemis . 1 - 3 . Male anal appendages , dorsal view and right side . 4 . Right lateral view of prothorax .

Pl. 16. — Male anal appendages of Malaysian species of Amphicnemis, dorsal view and right side