Monomorium balathir

This ant has been found at baits, in litter samples and on trees in savanna and forest habitats.

Identification
Bolton (1987) - This dark coloured, large-eyed and conspicuously hairy species is a very distinctive member of the group. In colour and eye size it is approached only by the Kenyan Monomorium manir, but this species is less densely pilose and has shorter scapes, SI 89 as compared with 95-97 in Monomorium balathir. Two other large-eyed Afrotropical species are known in this group which have the maximum eye diameter greater than 0.30 x HW, Monomorium katir and Monomorium holothir. Both these are yellow in colour and katir has only 2-3 pairs of hairs on the promesonotum besides having very large eyes (0.35-0.38 x HW). M. holothir has slightly shorter scapes (SI 92-94) than balathir, besides being much lighter in colour and somewhat smaller.

Distribution based on Regional Taxon Lists
Afrotropical Region: Burkina Faso.

Nomenclature

 *  balathir. Monomorium balathir Bolton, 1987: 378 (w.q.) BURKINA FASO.

Worker
Holotype. TL 2.3, HL 0.52, HW 0.39, CI 75, SL 0.38, SI 97, PW 0.26, AL 0.54.

Clypeal carinae widely divergent anteriorly. Prominent median portion of clypeus with its anterior margin concave. Anterior and lateral margins of median portion of clypeus separated by a pair of low, weakly projecting triangular prominences. Eyes relatively large, 0.31 x HW and with 7-8 ommatidia in the longest row. In full-face view the posterior margins of the eyes just in front of the midlength of the sides. In profile the maximum diameter of the eye much greater than the distance separating the anteriormost point of the eye from the closest point of the mandibular insertion. Head capsule in profile dorsoventrally flattened. With the head in full-face view the antennal scapes, when laid straight back from their insertions, failing to reach the occipital margin. Sides of head very shallowly convex and the broad occipital margin with only the faintest trace of concavity in full-face view. Promesonotum in profile shallowly convex and sloping posteriorly to the narrow but conspicuously impressed metanotal groove. Metanotal cross-ribs short but sharply defined. Propodeal spiracle minute and pinhole-like. Petiole node in profile subconical, high and narrow and narrowly rounded above. Subpetiolar process a small elongate lobe. Postpetiole more broadly rounded above than petiole, the anterior face of its node almost vertical, the posterior face much more shallowly sloping. In dorsal view both nodes broader than long. Standing pilosity dense and conspicuous on all dorsal surfaces, the promesonotum with 8-9 pairs and those at the pronotal humeri and midlength of the promesonotum notably elongate. Sides of head both in front of and behind eyes with projecting suberect to subdecumbent hairs. Entire body smooth and shining, unsculptured except for scattered minute hair-pits and metanotal short cross-ribs. Colour glossy dark brown, the appendages dull yellow.

Paratypes. TL 2.2-2.3, HL 0.50-0.52, HW 0.37-0.39, CI 73-76, SL 0.36-0.38, SI 95-97, PW 0.26, AL 0.54-0.55 (4 measured). As holotype but maximum diameter of eyes 0.30-0.32 x HW. Subpetiolar process may be reduced to a low narrow ridge. Promesonotal dorsum with 8-10 pairs of standing hairs.

Type Material
Holotype worker, Burkina Faso (U. Volta on label): Ougadougou, 6.ix. I970 (P. Room). Paratypes, 4 workers and 1 female with same data as holotype (BMNH; ).