Monomorium pulchrum

This species has been collected across a range of habitats, from Bushveld to Acacia woodlands.

Identification
Bolton (1987) - A member of the M. bequaerti complex in the M. monomorium species group. M. pulchrum is closest related to the darker coloured Monomorium bequaerti from Zaire. Of the species with 11 antennal segments these two form a close complex with Monomorium rosae, a common West and Central African form which is blackish brown to black in colour. M. pulchrum separates from bequaerti by colour and size, and by the fact that the nodes of both petiole and postpetiole are longer than broad in dorsal view in bequaerti, both broader than long in pulchrum.

Distribution based on Regional Taxon Lists
Afrotropical Region: Zimbabwe.

Nomenclature

 *  pulchrum. Monomorium (Lampromyrmex) pulchrum Santschi, 1926b: 238, fig. 3 (w.) ZIMBABWE. See also: Bolton, 1987: 406.

Worker
Bolton (1987) - TL 1.7-1.9, HL 0.44-0.48, HW 0.36-0.38, CI 78-82, SL 0.32-0.34, SI 87-92, PW 0.22-0.26, AL 0.50-0.54 (8 measured).

Clypeal carinae finely but sharply developed, widely separated and strongly divergent anteriorly. Anterior clypeal margin transverse to feebly convex between the apices of the carinae. Anterior and lateral faces of the projecting median portion of the clypeus separated by an obtuse angle, without projecting teeth. Fourth (basal) tooth of mandible much smaller than the third, reduced to a denticle. Maximum diameter of eye 0.18-0.21 x HW and with 5-6 ommatidia in the longest row. Outer ring of ommatidia enclosing more than one transverse row. In full-face view the eyes conspicuously in front of the midlength of the sides. Antennae with 11 segments; the antennal scapes, when laid straight back from their insertions, failing to reach the occipital margin. In full-face view the occipital margin very feebly concave medially. Promesonotum evenly shallowly convex in profile, the metanotal groove broad, deeply impressed and traversed by sharply defined ribs. Propodeal dorsum convex, highest approximately above the level of the small pinhole-like spiracle. Posteriorly the dorsum rounding broadly into the declivity. Petiole node high and quite narrowly subconical in profile, narrowly rounded above. Subpetiolar process a narrow longitudinal strip, the ventral margin of the petiole node shallowly convex behind the process but not strongly bulging downwards. Postpetiole in profile approximately as voluminous as the petiole, almost as high but distinctly more broadly rounded above. Anterior face of postpetiole shallowly convex, the posterior face much longer than the anterior and more or less fiat in profile, sloping at about 45°. In dorsal view both nodes distinctly broader than long, the postpetiole broader than the petiole. All dorsal surfaces of head and body with conspicuous fine standing hairs, the promesonotum with 6-7 pairs and the propodeum with 2-3 pairs. Sculpture absent except for metanotal cross-ribs and some faint shagreening on the pleurae. Colour of head and alitrunk glossy dull yellow to pale brown, the gaster somewhat darker brown.

Type Material
Bolton (1987) - Syntype workers, Zimbabwe: Sawmills, 27.xii. 1923 (G. Arnold) [examined].