Tetramorium politum

Known from rainforest, one collection was made from a nest in a rotten log.

Identification
Bolton (1977) - T. politum is the most specialized member of the ornatum-group in New Guinea and in its elongate scapes, rounded head and reduced sculpture it parallels the developments seen in Tetramorium bicolor (bicarinatum-group) and Tetramorium diligens (carinatum-group). However, the elongate petiole peduncle and downcurved propodeal spines characteristic of most species of the ornatum-group are retained. The tendency to shorten or reduce the frontal carinae in this group reaches its strongest expression in Tetramorium politum and the effect is enhanced by the extreme reduction in sculpture everywhere on the head. The frontal carinae are really no more strongly developed in such species as Tetramorium sculptatum but the appearance is not so striking here as the entire head is covered with closepacked longitudinal sculpture.

Distribution based on Regional Taxon Lists
Indo-Australian Region: New Guinea.

Nomenclature

 *  politum. Tetramorium politum Emery, 1897d: 568 (w.) NEW GUINEA. See also: Bolton, 1977: 107.

Worker
Bolton (1977) - TL 3.8, HL 0.88, HW 0.74, CI 84, SL 0.78, SI 105, PW 0.58, AL 1.08.

Mandibles feebly sculptured. Anterior clypeal margin entire, evenly convex. Frontal carinae short, extending back only to the level of the eyes. Occipital margin of head in full-face view rounded and evenly convex. Maximum diameter of eye c. 0.16. Antennal scapes long, SI > 100, the scapes surpassing the occipital margin when laid straight back along the head. Propodeal spines long, narrow and acute, slightly downcurved along their length. Metapleural lobes rounded, blunt. Petiole in profile with a long, curved anterior peduncle and a node which in profile is about as long as high, the dorsum feebly convex. Postpetiole in profile as high as petiole but narrower and more strongly convex dorsally (Fig. 23). Sculpture sparse, the integument mostly smooth. Clypeus with a strong median carina and with vestiges of others laterally. Head with median carina running from the clypeus to the level of the posterior margins of the eyes and with faint traces of other sculpture on each side of the carina, but otherwise the head unsculptured dorsally. Dorsal surfaces of alitrunk, petiole and postpetiole mostly smooth but with scattered faint rugulae present in places; sides of these areas more strongly sculptured than the dorsum but still only weakly marked. Gaster unsculptured. Very fine erect or suberect hairs present on all dorsal surfaces, those projecting from the dorsal (outer) surface of the hind tibiae short and curved, much shorter than the maximum tibial width. Colour uniform blackish brown, the legs and antennae lighter.

Type Material
Bolton (1977) - Holotype worker, New Guinea: Moraka (L. Loria) (probably in ).