Tetramorium meressei

Identification
Bolton (1980) - Together with Tetramorium psymanum, T. meressei forms a close species-pair within the dumezi-group characterized by smooth mandibles, entire clypeal margin, very dense long pilosity and a high postpetiole node which has a free vertical posterior face. The two are separated by the presence in T. meressei of propodeal teeth and rounded dorsal angles on the petiole. In T. psymanum the propodeum is angular, without developed teeth, and the dorsal petiolar angles are present. Apart from this T. psymanum is brown and has the dorsal alitrunk evenly sculptured, the rugulae on the propodeum and mesonotum being as dense and almost as strong as those on the pronotum. In contrast T. meressei is yellow and has mesonotal and propodeal sculpture much less dense and less intense than on the pronotum.

Distribution based on Regional Taxon Lists
Afrotropical Region: Democratic Republic of Congo, Ghana, Sudan.

Nomenclature

 *  meressei. Tetramorium meressei Forel, 1916: 422 (w.) DEMOCRATIC REPUBLIC OF CONGO. See also: Bolton, 1980: 349.

Worker
Bolton (1980) - TL 3.2-3.5, HL 0.70-0.80, HW 0.56-0.64, CI 79-82, SL 0.46-0.52, SI 77-83, PW 0.44-0.50, AL 0.92-1.00 (7 measured).

Mandibles smooth and shining with scattered small pits. Anterior clypeal margin entire, without trace of a median notch. Clypeus with three carinae, the median and a widely separated flanking pair. Frontal carinae feebly developed, fine and narrow, running back beyond the level of the posterior margins of the eyes but fading out on the occiput and merging with the remaining occipital sculpture. Maximum diameter of eye 0.15-0.17, about 0.25-0.27 x HW and with 9-10 ommatidia in the longest row. Head in fullface view roughly rectangular in shape, the sides more or less parallel, not evenly convex. Propodeum armed with a pair of short, small triangular teeth which are shorter and much narrower than the triangular metapleural lobes. Petiole node in profile high, narrowing from base to apex as the anterior and posterior faces converge dorsally, and with the evenly convex dorsum very short, much shorter than the height of the tergal portion of the node. Both the antero- and posterodorsal angles of the node blunt, the dorsum rounding into the anterior and posterior faces. In dorsal view the petiole node subglobular, rounded and slightly broader than long. Postpetiole in profile with a steep and fairly evenly convex anterior face, a high, narrowly rounded dorsum and an abrupt vertical posterior face. Dorsum of head longitudinally rugulose, the rugulae spaced out and with some cross-meshes and anastomoses occipitally but without a strong reticulum. A fine superficial granular or punctulate ground-sculpture present between the rugulae, not conspicuous. Pronotal dorsum irregularly and quite sharply rugulose, formiing a loose reticulum in places, the rugulae here more strongly developed than those on the dorsal head. Mesonotum and propodeum much less strongly sculptured, with superficial rugulae. Petiole, postpetiole and gaster dorsally unsculptured, or the last with the faintest traces of shagreening basally, very inconspicuous. Sides of petiole and postpetiole usually with a few faint rugulae, at least anteriorly. All dorsal surfaces of head and body with an abundance of fine acute elongate curved hairs. Sides of head in full-face view with > 10 projecting hairs breaking the outline behind the eyes. Scapes with dense fine suberect pubescence on the leading edges. Dorsal (outer) surfaces of middle and hind tibiae with erect to suberect elongate fine hairs similar to those on the dorsum of the body. Colour uniform pale yellow.

Type Material
Bolton (1980) - Syntype workers, ZAIRE (Koh!) (MHN, Geneva) [examined].

References based on Global Ant Biodiversity Informatics

 * Wheeler W. M. 1922. Ants of the American Museum Congo expedition. A contribution to the myrmecology of Africa. II. The ants collected by the American Museum Congo Expedition. Bulletin of the American Museum of Natural History 45: 39-269.