Messor striatifrons

Identification
A fairly distinctive member of the group of species centering on Messor capensis, striatifrons is characterized by its relatively long low propodeum and convex head sides. The shape of the head is not duplicated in other African species but Messor denticornis has a similarly proportioned propodeum. However, in this last-named species the eyes are larger, with a range of 0.21-02.5 x HW. (Bolton 1982)

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

Castes
Known only from the worker caste.

Nomenclature

 *  striatifrons. Messor denticornis var. striatifrons Stitz, 1923: 149 (w.) NAMIBIA. Raised to species: Bolton, 1982: 353.

Worker
Bolton (1982) - Medium to Large, HW 2.84- > 3.75.

Anterior clypeal margin usually shallowly convex medially but sometimes a weak central indentation of the margin is present. With the head in full-face view the sides convex. Generally the convexity is distinct in larger workers but tends to be less marked in sma!ler individuals; infrequently the reverse is true and medium sized workers show the convexity more strongly than larger specimens. Occipital margin shallowly indented medially, the indentation best developed in large workers and slowly disappearing with decrease in size. Within the HW range 2.84-3.76 the maximum diameter of the eye is 0.52--0.68, about 0.16--0.18 x HW, and the CI range is 104-114. Propodeum in profile relatively long and low, usually rounded at the junction of dorsum and declivity but quite frequently right-angled or projecting into a broad short tooth which is really no more than a projection of the right-angle. Dorsum of head sculptured with extremely fine dense longitudinal rugulae which in the strongest sculptured individuals are very close packed. Spaces between the rugulae with fairly conspicuous ground-sculpture of fine punctures. In medium sized workers, and quite frequently in maximum sized workers also, the sculpture on the dorsal head is modified by a weakening of the rugular component and an intensification of the punctures, so that in some the rugular component is supressed and the head appears reticulate-punctate everywhere or almost everywhere. Dorsal alitrunk rugulose, the direction of the sculpture variable but usually stronger on the propodeum than elsewhere. First gastral tergite unsculptured or at most with the faint superficial patterning so commonly seen in this genus. All dorsal surfaces of head and body with numerous standing hairs; evenly distributed hairs conspicuous on first gastral tergite. Colour medium to dark brown, commonly uniform but often with the gaster darker, blackish brown.