Tetramorium bicolor

Specimens have been found in forest habitats, in a twig nest and as a ground forager.

Identification
Bolton (1977) - The construction of the petiole and general habitus shows that bicolor is very closely related to Tetramorium pacificum and its allies, but the reduced sculpture and distinct colouring immediately separates bicolor. It is one of three bicoloured (yellow and black) species occurring in New Guinea. One of these, Tetramorium diligens, belongs to the carinatum-group and hence is separable by its 11-segmented antennae and spatulate sting appendage. The other is Tetramorium tricarinatum, which is very closely related to bicolor but much more strongly sculptured, and which possesses three carinae on the cephalic dorsum between the frontal carinae, running from the posterior clypeal margin almost to the occiput.

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

Nomenclature

 *  bicolor. Tetramorium bicolor Viehmeyer, 1914b: 39 (w.) NEW GUINEA. See also: Bolton, 1977: 97.

Worker
Bolton (1977) - TL 3.6-3.8, HL 0.84-0.90, HW 0.68-0.76, CI 80-84, SL 0.64-0.72, SI 76-80, PW 0.52-0.56, AL 0.98-1.08 (2 measured).

Mandibles smooth with scattered pits. Anterior clypeal margin with a median notch or impression. Clypeus with three strong longitudinal carinae. Frontal carinae feeble but extending back almost to occiput. Median carina of head distinct only to level of posterior margins of eyes, behind this rapidly fading out or absent. Eyes prominent, maximum diameter C. 0.17-0.18. Pronotal corners angular in dorsal view. Metanotal groove absent. Propodeal spines long, narrow and acute, the metapleural lobes triangular and upcurved. Petiole in profile with the tergal portion longer than high, the anterior and dorsal faces united through a curve, not separated by an angle. Dorsum convex and sloping upwards posteriorly so that the posterodorsal angle is on a higher level than the anterodorsal. Head either completely unsculptured dorsally except for the median carina or at most with one or two short, fine rugulae here and there on the surface. Pronotal dorsum with a few rugae anteriorly and laterally but the middle of the pronotum and the whole mesonotum smooth and very shiny. Propodeal dorsum reticulate-rugulose. Petiole and postpetiole each with some rugae, predominantly or entirely longitudinal. Gaster unsculptured. All dorsal surfaces of head and body with abundant erect, long hairs. Colour very distinctive, the head and gaster black or blackish brown, the alitrunk, pedicel and appendages bright yellow, the colours strongly contrasting.

Type Material
Bolton (1977) - Holotype worker, New Guinea: Wareo [examined].