Tetramorium wadje

Identification
Bolton (1980) - This small species has no known close relatives but may perhaps be descended from the simillimum-group. Most of the reductions seen in the poweri-complex of that group are taken to extremes in wadje but, and this is critical, the short blunt hairs characteristic of all members of the simillimum-group are absent in T. wadje, being replaced by minute appressed fine hairs all over the body. Because of this T. wadje is excluded from that group and is placed here with Tetramorium convexum, purely for convenience. The two species have a number of characters in common as noted in the species-group diagnosis, but they are easily separated as T. convexum has numerous fine hairs on the dorsal surfaces of the head and body and lacks propodeal armament.

Distribution based on Regional Taxon Lists
Afrotropical Region: Ghana.

Nomenclature

 *  wadje. Tetramorium wadje Bolton, 1980: 322 (w.q.) GHANA.

Worker
Holotype: TL 2.3, HL 0.55, HW 0.45, CI 82, SL 0.32, SI 71, PW 0.32, AL 0.64. Paratypes (6 measured): TL 2.2-2.3, HL 0.54-0.56, HW 0.44-0.45, CI 81-83, SL 0.31-0.34, SI 69-75, PW 0.31-0.32, AL 0.62-0.64. Maximum diameter of eye 0.11-0.12, about 0.24-0.27 x HW and with 5-6 ommatidia in the longest row.

Mandibles smooth and shining with scattered small pits. Anterior clypeal margin entire, without trace of a median notch. Median clypeal carina weakly defined but present. Frontal carinae absent, the frontal lobes not extending beyond the limits of the impressions within which the antennae are articulated. Antennal scrobes completely absent, the head evenly transversely convex between the eyes. Antennal scapes short (SI range 69-75 in type-series). Eyes moderate, maximum diameter 0.12, about 0.27 x HW and with 6 ommatidia in the longest row. With the alitrunk in profile the promesonotal dorsum more or less flat and on a slightly higher level than the propodeal dorsum so that there is a shallow step-down between the two surfaces. Propodeal dorsum very shallowly convex and ending in a pair of very short, broad teeth which are shorter than the low blunt metapleural lobes. Petiole in profile with a short, thick anterior peduncle which has a conspicuous tooth ventrally. Tergal portion of node slightly higher than the dorsal length, the node narrowing slightly from base to apex and with the posterodorsal angle more bluntly rounded than the anterodorsal. In dorsal view the node very slightly broader than long. Dorsum of head with numerous very fine weak irregular longitudinal rugulae superimposed upon a finely punctulate or granular groundsculpture. Dorsal surfaces of alitrunk, petiole and postpetiole unsculptured or at most with vestigial superficial shagreening, the surface to a large extent shining. First gastral tergite unsculptured except for minute pits from which the hairs arise. Standing hairs absent from all dorsal surfaces of the head and body, but all dorsal surfaces with appressed pubescence or appressed very short, fine hairs. Appendages only with appressed fine pubescence. Colour uniform dull yellow.

Paratypes: In some the propodeal spines and metapleural lobes are somewhat more strongly developed than in the holotype and the sculpture of the dorsal alitrunk may be more or less effaced.

Type Material
Holotype worker, Ghana: Aburi, 1.iii.1969 (P. Room). Paratypes. Ghana: 2 workers and | female with same data as holotype; 3 workers, Tafo, K2, 23.ix.1975 (C. Campbell). Nigeria: 1 worker, C.R.I.N., Onipe, tree 19/18, 14.1.1975, blackpod project (B. Taylor). (BMNH; ).

References based on Global Ant Biodiversity Informatics

 * Bolton B. 1980. The ant tribe Tetramoriini (Hymenoptera: Formicidae). The genus Tetramorium Mayr in the Ethiopian zoogeographical region. Bulletin of the British Museum (Natural History). Entomology 40: 193-384.