Tetramorium dominum

The single specimen of this remarkable species was included in a sample of Tetramorium clunum collected on sandy soil in which the latter was nesting. Its relationship, if any, with T. clunum is not known, but I suspect that it was just a stray which found its way into the sample by dint of being in the wrong place at the right time.

Identification
Bolton (1980) - A member of the Tetramorium capense species group. The only known close relative of T. dominum is Tetramorium capense and the two are easily separated by the distinctive pilosity of the former, as described above and as discussed under T. capense.

Distribution based on Regional Taxon Lists
Afrotropical Region: South Africa.

Nomenclature

 *  dominum. Tetramorium dominum Bolton, 1980: 360, fig. 136, 139 (w.) SOUTH AFRICA.

Worker
Holotype: TL 3.9, HL 0.93, HW 0.90, CI 97, SL 0.72, SI 80, PW 0.60, AL 1.02.

Mandibles finely longitudinally striate. Anterior clypeal margin with a conspicuous median notch. Median clypeal carina fine and sharp, flanked by 1-2 weaker carinae on each side. Frontal carinae sinuate, widely separated, running back to a point just behind the level of the posterior margins of the eyes and surmounted to this point by a narrow raised rim or crest. On the occiput the carinae fade out or become indistinguishable from the remaining sculpture. Antennal scrobes represented only by a broad shallow concavity in the sides between the eyes and the frontal carinae on each side. Eyes relatively small, maximum diameter 0.16, about 0.18 x HW and with 8 ommatidia in the longest row. Head in full-face view almost as broad as long (CI, above) with shallowly convex sides which are distinctly convergent anteriorly (Fig. 136). Behind the eyes the sides convex and rounding evenly into the occipital margin. Propodeal spines in profile narrow and acute, longer than the broad rounded metapleural lobes but much narrower than them. Petiole in profile with a thick anterior peduncle, the anterior and dorsal faces of the node meeting in a right-angle, the posterodorsal angle slightly more obtuse. In dorsal view the node about as broad as long, narrowly rounded anteriorly. Dorsum of head densely and quite regularly finely longitudinally rugulose, the rugulae tending to multiply at eye level so that whilst 11 are present between the frontal carinae at the level of the anterior margin of the eye, there are 17 at the level of the posterior margin. Dorsal rugulae diverge to left and right on occiput and arch around the occipital corners. There is no ruguloreticulum developed. Sides of head above, behind and below eyes longitudinally rugulose. Ground-sculpture on dorsum a fine superficial punctulation. Dorsal alitrunk more finely rugulose than head; those on pronotum transverse and arched, longitudinal on remainder of alitrunk; everywhere with a fine superficial punctulate ground-sculpture. Petiole and postpetiole dorsally with vestigial rugulae, first gastral tergite unsculptured. Dorsal surfaces of head and alitrunk with abundant very short stout blunt hairs, distinctly shorter than half the maximum diameter of the eye. In striking contrast the first gastral tergite with abundant long fine acutely pointed hairs which are narrower than those on the alitrunk and about 3-4 times longer. Colour yellowish brown, light.

Type Material
Holotype worker, South Africa: Cape Prov., Willowmore, 1.xii.1976, on sandy soil (C. F. Jacot-Guillarmod).