Polyrhachis compressicornis

Smith, F., 1860, Descriptions of new species of hymenopterous insects collected by Mr. A. R. Wallace at Celebes. (Part Formicidae), Journal of the Proceedings of the Linnean Society of London, Zoology 5, pp. 57-93 : 69-70

2. Polyrhachis compressicornis .

P. niger et vestitus pube cinerea; thoraee spinis duabus acutis antice armato; abdominis squamula spinis duabus brevibus armata; pedibus ferrugineis.

Female. Length 51/2 lines. Black and densely clothed with cinereous pile, which has a silvery brightness in certain lights; the mandibles shining black, and longitudinally striated; the antennæ inserted at the sides of two prominent carinæ; the scape compressed, much broader than usual, with the apex widest and thinly covered with short pale glittering pubescence. Thorax: the spines at the lateral angles of the prothorax short, stout, and acute; the mesothorax very convex, with an abbreviated shining carina in the middle anteriorly; the metathorax transverse, abruptly truncated, slightly concave in the middle above; the legs ferruginous, with their articulations and tarsi fuscous. Abdomen ovate; the peduncle subtriangular, a stout, short, acute spine at the lateral angles.

Worker. Length 41/4 lines. Only differs in having the thorax flattened above, with the lateral margins slightly raised; the scape of the antennæ compressed, as in. the female.