Monomorium springvalense

One of the few collections of this species was taken in a pitfall trap in a grassland.

Identification
Bolton (1987) - A member of the M. leopoldinum complex in the M. monomorium species group. M. springvalense is very closely related to Monomorium borlei within the leopoldinum-complex but the two are separated by the darker colour, larger propodeal spiracle and even sparser pilosity of the latter.

Distribution based on Regional Taxon Lists
Afrotropical Region: Zimbabwe.

Nomenclature

 *  springvalense. Monomorium oscaris r. springvalense Forel, 1913a: 136 (w.) ZIMBABWE. Subspecies of musicum: Emery, 1922e: 173. Raised to species: Santschi, 1926b: 236; Bolton, 1987: 412.

Worker
Bolton (1987) - TL 2.0-2.1, HL 0.50-0.52, HW 0.40-0.41, CI 77-80, SL 0.36-0.37, SI 90, PW 0.26-0.30, AL 0.53-0.58.

Clypeal carinae sharply developed and conspicuous; widely divergent anteriorly. Anterior margin of prominent median portion of clypeus transverse to shallowly concave, usually with a feebly crenulate appearance. The anterior margin is bounded on each side by a low triangular prominent angle at the apex of each clypeal carina, the projecting angle separating the anterior and lateral margins of the median portion of the clypeus. Maximum diameter of eye 0.22-0.23 x HW and with 6-7 ommatidia in the longest row. Antennal scapes, when laid straight back from their insertions, failing to reach the occipital margin. With the head in full-face view the eyes situated conspicuously in front of the midlength of the sides; the sides behind the eyes weakly convex and the broad occipital margin shallowly concave medially. Promesonotum evenly shallowly convex in profile, sloping posteriorly to the narrow and only weakly impressed metanotal groove. Metanotal cross-ribs short but distinct. Propodeal spiracle of moderate size, not reduced to a mere pinhole nor very large and dominating the side of the sclerite. Propodeal dorsum rounding broadly and evenly into the declivity. Subpetiolar process a small anteroventral lobe which peters out posteriorly. Node of petiole in profile quite thickly subconical, the anterior and posterior faces both very fully convex and the node bluntly rounded above. Postpetiole smaller and lower than petiole, more broadly rounded dorsally but with relatively steep anterior and posterior faces, both of which are nearly vertical. Standing hairs present on all dorsal surfaces but relatively sparse on the alitrunk; the promesonotum with only 4 pairs. Sculpture entirely absent except for scattered hair-pits and metanotal cross-ribs. Alitrunk yellow, the head and gaster with a brownish tint; usually the gaster slightly darker in shade than the head.

Type Material
Bolton (1987) - Syntype workers, Zimbabwe: Springvale 6.x.1912, no. 111 (G. Arnold) [examined].