Tetramorium semireticulatum

Known only from Arnold's 1915 type series.

Identification
Bolton (1980) - At first glance this obscure little species seems to belong to the simillimum-group, but its notched clypeus and fine pilosity exclude it from there. Considering the whole ant, it shows a number of different characters together which individually are well developed in various other groups, but nowhere except here are they all found in combination. It is thus an overabundance of specialized characters rather than a lack of them which makes T. semireticulatum impossible to place at present.

Distribution based on Regional Taxon Lists
Afrotropical Region: Zimbabwe.

Nomenclature

 *  semireticulatum. Tetramorium semireticulatum Arnold, 1917: 319 (w.m.) ZIMBABWE. Arnold, 1926: 265 (q.). Senior synonym of politum: Bolton, 1980: 361.
 * politum. Tetramorium semireticulatum var. politum Arnold, 1948: 225 (w.) ZIMBABWE. [Unresolved junior primary homonym of politum Emery, above.] Junior synonym of semireticulatum: Bolton, 1980: 361.

Worker
Bolton (1980) - TL 2.3-2.9, HL 0.60-0.72, HW 0.52-0.63, CI 86-90, SL 0.44-0.54, SI 85-91, PW 0.38-0.48, AL 0.66-0.82 (12 measured).

Mandibles longitudinally striate. Anterior clypeal margin with a conspicuous median notch or impression. True frontal carinae very short, ending at or in front of the level of the anterior margin of the eye, only rarely extending slightly further back and with considerable variation in a single series. In some specimens the carinae may appear longer but this is an illusion caused by the presence of rugulae on the dorsum and their absence from the sides of the head ; these rugulae are not connected to the frontal carinae. Eyes small, maximum diameter 0.09-0.12, about 0.16-0.19 x HW and with 4-6 ommatidia in the longest transverse row. In profile the eye usually with a small prominence or point at the anteroventral corner. Propodeum in profile armed with a pair of short triangular teeth which are at most as long as the metapleural lobes, usually shorter than them. Petiole in profile with the anterodorsal angle almost or quite right-angular, the posterodorsal angle more obtuse or rounded. In dorsal view the node generally slightly broader than long but in some about as broad as long. All dorsal surfaces of head, alitrunk, petiole, postpetiole, and at least the basal third of (but sometimes all of) the first gastral tergite blanketed by a very dense fine conspicuous reticulate-puncturation which dominates any other sculpture which may be present. Dorsum of head with a few fine, feeble longitudinal rugulae and dorsal alitrunk also with some weak rugulae which are usually confined to the pronotum, generally forming a sparse reticulum anteriorly. All dorsal surfaces of head and body with a number of fine acute quite short hairs, but the scapes and tibiae only with minute decumbent to appressed pubescence. Colour yellowish brown to mid-brown, sometimes with a dull reddish tint.

Type Material
Bolton (1980) - Syntype workers, male, RHODESIA: Bulawayo, Hillside, 9.v.1915 (G. Arnold) [examined].

References based on Global Ant Biodiversity Informatics

 * IZIKO South Africa Museum Collection