Monomorium fastidium

The type material is listed as being found in eucalyptus litter. Many subsequent collections are from grassland habitats.

Identification
Bolton (1987f) - A member of the M. boerorum complex in the M. monomorium species group. A minute yellow species close to and slightly larger than Monomorium mictilis, but lacking the depressed head capsule of that species and having the promesonotum somewhat more convex. Apart from this the head in mictilis tends to be somewhat narrower (CI 72-76 as opposed to CI 76-79 in fastidium) and slightly different in shape. Whereas in fastidium the head in full-face view is broadest behind and narrows anteriorly, the head in mictilis is broadest immediately behind the eyes and gradually narrows both anteriorly and posteriorly from this point.

Distribution based on Regional Taxon Lists
Afrotropical Region: South Africa.

Nomenclature

 *  fastidium. Monomorium fastidium Bolton, 1987: 389 (w.q.) SOUTH AFRICA.

Worker
Holotype. TL 1.4, HL 0.42, HW 0.33, CI 79, SL 0.27, SI 82, PW 0.20, AL 0.42.

Clypeal carinae distinctly developed, divergent anteriorly, reaching the anterior margin but not terminating in denticles or angular projections. In full-face view the median portion of the clypeus prominent and the anterior border of the prominence more or less transverse. Maximum diameter of eye 0.21 x HW. In profile the eye longer than high and consisting of an outer ring of ommatidia enclosing a single longitudinal row of only 3 ommatidia. In full-face view the eye conspicuously in front of the midlength of the sides of the head. Antennae with 11 segments. Antennal scapes, when laid straight back from their insertions, failing to reach the occipital margin. Head capsule in full-face view broadest posteriorly, the sides evenly and gradually narrowing anteriorly and the eyes situated in front of the broadest part of the head. In profile the ventral surface of the head convex, the convexity only shallow but noticeably greater than the convexity of the cephalic dorsum immediately behind eye-level. Promesonotum in profile not strongly convex, sloping very shallowly to the distinctly impressed and relatively broad metanotal groove; the latter with conspicuous cross-ribs. Propodeum highest immediately behind the metanotal groove then falling away posteriorly in an even, smoothly convex curve, without differentiation into dorsum and declivity. Propodeal spiracle minute and pinhole-like. Anterior peduncle of petiole short and stout, with a small lobulate ventral process. Petiole node with anterior face longer and somewhat more shallowly sloped than posterior face; the node narrowly but bluntly rounded above. Postpetiole smaller and slightly lower than petiole, much more broadly rounded dorsally. All dorsal surfaces of head and body with standing hairs, the promesonotum with only 3 pairs. Anterior margin of pronotum without a pair of standing hairs between those at the humeri. Unsculptured except for the metanotal cross-ribs. Colour uniform dull pale yellow.

Paratypes. TL 1.4, HL 0.42-0.43, HW 0.32-0.33, CI 76-79, SL 0.26-0.28, SI 81-85, PW 0.20-0.21, AL 0.42-0.44 (10 measured). As holotype but some paratypes have a fourth promesonotal pair of standing hairs.

Type Material
Holotype worker, South Africa: E. Cape Prov., Walmer nr Port Elizabeth, 3.iii.1969, eucalypt litter, M374 (W. L. Brown). Paratypes. 10 workers and 5 alate females with same data as holotype (MCZ; ).

References based on Global Ant Biodiversity Informatics

 * Bolton B. 1987. A review of the Solenopsis genus-group and revision of Afrotropical Monomorium Mayr (Hymenoptera: Formicidae). Bulletin of the British Museum (Natural History). Entomology 54: 263-452.