Strumigenys irrorata

Identification
Bolton (1983) - Immediately recognized by its unique (in Africa) pre apical dentition, irrorata is the only member of the rogeri-group having a single preapical tooth on each mandibular blade. The usual count in the group is 2 preapical teeth on each blade but a few species have one left and two right preapical teeth.

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

Nomenclature

 *  irrorata. Strumigenys (Strumigenys) irrorata Santschi, 1913b: 257 (diagnosis in key) (w.) SOUTH AFRICA. Santschi, 1914e: 29 (w.). See also: Brown, 1954k: 33; Bolton, 1983: 375; Bolton, 2000: 593.

Worker
Bolton (1983) - TL 1.9-2.1, HL 0.47-0.54, HW 0.38-0.43, CI 76-83, ML 0.19-0.23, MI 40-43, SL 0.24-0.28, SI 62-70, PW 0.24-0.27, AL 0.50-0.56 (10 measured).

Apical fork of each mandibular blade with 2 spiniform teeth, without intercalary teeth or denticles. Pre apical armament of a single spiniform tooth on each blade which corresponds to the proximal preapical tooth in related species; the distal preapical teeth lost. Upper scrobe margins strongly divergent behind the frontal lobes, the eyes not visible in full-face view. Eyes very small, conspicuously much smaller than the maximum width of the scape. Preocular notch absent, the ventral surface of the head without a preocular transverse groove or impression. Scapes short, weakly curved, their anterior margins shallowly convex and equipped with a row of short spoon-shaped to scale-like hairs. Ground-pilosity of cephalic dorsum of dense short spoon-shaped hairs which are broad and appear scale-like in full-face view. Hairs fringing the upper scrobe margins the same as those on the dorsum, and about equal in size to the projecting hairs on the leading edges of the scapes. Dorsum of head with 6 standing hairs, arranged in a transverse row of 4 close to the occipital margin and a more anteriorly situated pair. Dorsum of head densely reticulate-punctate. Pronotal humeri each with a single long fine flagellate hair. Mesonotum with a single pair of stout standing hairs which are weakly clavate apically. Ground-pilosity of dorsal alitrunk of sparse small hairs which are spatulate to narrowly spoon-shaped. Propodeal teeth subtended by broad infradental lamellae. Metanotal groove not impressed. Sides of alitrunk mostly smooth, sometimes with vague traces of sculpture on the pronotal sides and usually with weak punctulae on the pleurae and propodeum. Pronotal dorsum longitudinally rugulose, the rest of the dorsal alitrunk punctate. Dorsum of petiole node punctate, the postpetiole smooth and shining. Spongiform appendages of pedicel segments well developed, the petiole with a broad ventral spongiform strip and the postpetiole with large ventral and lateral lobes. Basigastral costulae short but sharply defined. Dorsal surfaces of petiole, postpetiole and gaster with stout standing hairs which are weakly clavate apically. Colour medium to dark brown.

Type Material
Bolton (1983) - Holotype worker, SOUTH AFRICA: Natal, Zululand, Lake Sibayi (I. Triigardh) [examined].