Descriptions and records of South-East Asiatic Odonata (II) Author M. A. Lieftinck text Treubia 1940 1940-01-01 17 4 337 392 journal article http://doi.org/10.5281/zenodo.3571116 a02f182b-32e4-4649-afe0-983cb21ceb9e 3571116 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.