Tetramorium vertigum

A forest species that has been found nesting in rotten wood.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Indonesia, Philippines, Sulawesi.

Nomenclature

 *  vertigum. Tetramorium vertigum Bolton, 1977: 84, fig. 8 (w.) INDONESIA (Sulawesi).

Worker
Holotype. TL 4.0, HL 0.96, HW 0.90, CI 94, SL 0.90, SI 100, PW 0.70, AL 1.20.

Mandibles longitudinally striate. Sides of head slightly convex, the occipital margin broadly but shallowly concave. Frontal carinae extended behind the level of the eyes but posteriorly petering out and becoming confused with the sculpture on the vertex. Scrobes narrow and poorly defined, not capable of accommodating the scapes, which are long, SI about 100. Propodeum with a pair of acute spines, the metapleural lobes triangular. Node of petiole in profile longer than high, shaped as in figure, the postpetiole lower and broadly rounded. In dorsal view the petiole node roughly oval, longer than broad, somewhat broader behind than in front and slightly flattened posteriorly. Postpetiole in dorsal view subglobular, slightly broader than long. Dorsum of head behind level of eyes and entire dorsal alitrunk very coarsely reticulate-rugose, the reticulations raised and very conspicuous. Anterior portion of cephalic dorsum with the longitudinal component predominating. Sides of petiole with coarse rugae which are mostly directed diagonally, the dorsum with a median unsculptured longitudinal strip. Postpetiole and gaster unsculptured, smooth. All dorsal surfaces of head and body with numerous long, erect fine hairs which are acute apically. These hairs densest on the head and alitrunk, the longest being distinctly longer than the maximum diameter of the eye. Colour a very dark brown, almost black.

Paratypes. As holotype but in some the mandibular striation less distinct and the rugae on the sides of the petiole irregular. Size range: TL 3.6-4.2, HL 0.90-1.02, HW 0.80-0.92, CI 89-94, SL 0.84-0.90, SI 97-105, PW 0.60-0.70, AL 1.12-1.22. In general the smaller workers have relatively longer scapes than the larger workers.

Type Material
Holotype worker, Sulawewsi (S. Celebes on data label): S., Balampesoang Forest, 5-8 km NE. Tanete, 400 m, 8-10.vii.1972, rot. wood; degrad. rain for. (W. L. Brown). Paratypes. 14 workers with same data as holotype (MCZC; ).