Polyrhachis laevissimus

Smith, F., 1859, Catalogue of hymenopterous insects collected by Mr. A. R. Wallace at the Islands of Aru and Key., Journal of the Proceedings of the Linnean Society of London, Zoology 3, pp. 132-158 : 141

11. Polyrhachis laevissimus .

P. niger, laevis nitidusque; metathorace bispinoso, petioli squamula quadrispinosa, pedibus ferrugineis.

Worker. Length 2 3 / 4 lines. Black, very smooth and shining; the legs ferruginous, with the coxae, articulations, and the tarsi black. The thorax not flattened above, or margined at the sides; the division between the pro- and mesothorax distinct, that between the meso- and metathorax not discernible, the latter with two erect acute spines; the scale of the petiole with four short acute spines. Abdomen globose.

Hab. Aru.

This species is very like P. mucronatus ; on close examination, however, it is seen to be very distinct: it may be at once distinguished by its larger head, which is wider than the thorax, rounded behind the eyes, and widely emarginate behind.