Tetramorium ataxium Bolton

Type location Nigeria (Bolton, 1980: 295, illustrated, head and alitrunk-pedicel profile; worker) .

Bolton's description (1980), with slightly larger dimensions (TL 3.0-3.5 mm), is at .

WORKER (drawn specimen) - TL 2.86 mm, HL 0.67, HW 0.61, SL 0.56, PW 0.42 (in my guide as Tetramorium species T¹)
Colour dark red-brown. Superficially similar to Tetramorium lucayanum, but with a smaller eye, and the margin of the alitrunk not clearly defined. Sculpturation of the head, alitrunk and pedicel more reticulate and less rugose. Clypeus very convex, with a pronounced medial carina, projecting slightly on the anterior margin. Propodeal spines long, acute and triangular pointing upwards; metapleural lobes fairly large, upward pointing triangles. Petiole with a more rounded anterior face.

Bolton (1980) described the holotype worker and 6 paratype workers from Nigeria, at IITA (B.R. Critchley, 16-23.ix.1974), other findings from Mokwa (B. Labesikan) and Ile Ife (J.T. Medler). Nests in the soil and in dead wood on the ground and forages on the wood. Also at CRIN (B. Bolton; myself) - I found it on a cocoa trunk at 100 cm above ground, perhaps tending Homoptera; also on rotting blackwood at Block E6/1.

Listed by Bolton (1980) from Ghana at Mampong, Legon, Kibi, Mt. Atewa (D. Leston), Mampong (P.M. Room) and CRIG (B. Bolton). Since described as widespread from their leaf litter collections (140 workers plus 4 from soil samples, at 11 sites) in the semi-deciduous forest zone, by Belshaw & Bolton (1994b).

Curiously, although under Tetramorium angulinode Bolton outlined at some length how he had established specimens collected in Guinea by Lamotte and thought by Bernard (1952) to be of "Tetramorium humerosum" actually were of this species, he (Bolton) made no reference to the story under ataxium. The Guinea records given by Bernard (1952) were all from Mt. Nimba by Lamotte - several workers (TL 2.2-3.0) from each of Kéoulenta, savanna (common); station B8.8, N'Zo; also 4 alate queens from station B8.8 (TL 3.7-4.0). Bernard defined a new bicoloured subspecies "muscicola" of "humerosum", these specimens were assigned to Tetramorium coloreum by Bolton.

Other countries, all West African, listed by Bolton (1980) were Ivory Coast, at the Palmeraie de Lame (36 workers, T. Diomande, 23.i.1976) and Lamto (J. Lévieux).

The photomontage is of a specimen from Congo, Brazzaville, pitfall trap t1.13, 19.viii.2007, collected by Yves Braet & Eric Nzassi, 2007.

Other images can be seen in the folders at - Congo - t 1.13 and t 1.16

The photomontage is of a second specimen from Congo, Brazzaville, pitfall trap t1.6, 19.viii.2007, collected by Yves Braet & Eric Nzassi, 2007.