Monomorium excelsior

One collection of this species was found in Strandveld habitat. Little else is known about the biology of this species.

Identification
Bolton (1987) - A member of the M. tchelichofi complex in the M. salomonis species group. First described by Arnold (1926) as a variety of Monomorium tchelichofi, excelsior clearly ranks as a separate species. Not only do the two have very different distributions of pilosity but also their dimensions show marked differences. Compare the measurements given in the description with those of tchelichofi (HW 0.74-0.82, CI 82-86, SI 95-100). Also the eyes of tchelichofi tend to be somewhat smaller, maximum diameter 0.20-0.23 x HW, and the dorsal alitrunk is more evenly and more strongly sculptured than in excelsior.

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

Nomenclature

 *  excelsior. Monomorium tchelichofi var. excelsior Arnold, 1926: 227 (w.m.) SOUTH AFRICA. Raised to species and senior synonym of speculiceps: Bolton, 1987: 344.
 * speculiceps. Monomorium (Xeromyrmex) speculiceps Santschi, 1928f: 191, fig. 3 (w.) SOUTH AFRICA. Junior synonym of excelsior: Bolton, 1987: 344.

Worker
Bolton (1987) - TL 3.3-3.5, HL 0.84-0.92, HW 0.64-0.72, CI 76-80, SL 0.78-0.82, SI 114-122, PW 0.42-0.47, AL 0.96-1.06 (5 measured).

Anterior margin of median portion of clypeus transverse to extremely shallowly concave in full-face view, never notched medially. Eyes of moderate size, the maximum diameter 0.22-0.25 x HW and with 10 ommatidia in the longest row. Antennal scapes relatively long, SI > 110. Alitrunk appearing long and low in profile, the promesonotal dorsum forming an even shallow convexity from front to back and sloping posteriorly to the weakly impressed metanotal groove. Petiole node cuneate in profile, narrowly rounded above. Cephalic dorsum behind the frontal lobes with 3-4 pairs of hairs straddling the midline, the occipital margin with a further 2-3 pairs arranged in a roughly transverse row; the outermost of these hairs very close to the occipital corner. A single pair of relatively long standing hairs present at the pronotal humeri and another, shorter, pair situated anteriorly on the mesonotal dorsum. Petiole node with one pair of backward directed hairs, postpetiole with 3-4 pairs. First gastral tergite with standing hairs numerous and distributed more or less evenly over the sclerite. Head smooth and very glossy, sculptured only with faint vestiges of fine superficial reticular patterning. Pronotal dorsum with superficial reticular patterning or with feeble reticulation. Mesonotum as pronotum or the reticulation somewhat more distinct. Propodeal dorsum weakly shagreenate-punctulate. Sides of alitrunk reticulate to reticulate-shagreenate, the pronotum much more weakly sculptured than the remainder. First gastral tergite unsculptured or with faint superficial reticulate patterning basally. Colour glossy chestnut-brown.

Type Material
Bolton (1987) - Syntype workers, males, South Africa: Cape Prov., Matroosberg, Hex River Mts, 5500-7000 ft (= 1677-2134 m), i.1917 (R. W. Tucker) [examined].