Pheidole saxicola Wheeler

Major - Minor - Type location Zaïre (Wheeler, 1922: 138, illustrated, major & minor) .

Described from numerous specimens taken by Lang, Chapin, and Bequaert, at Zambi, (type locality) and by the latter at Boma.

MAJOR - length 5.5 to 6 mm. Head subrectangular, nearly 3 mm. long and very nearly as broad, scarcely broader behind than in front, with straight subparallel sides, rectangular anterior corners, deeply and angularly excised posterior border, and deep occipital and frontal groove. In profile the occipital region is very feebly depressed and the eyes are small, feebly convex, and at the anterior third of the sides. Gula anteriorly with prominent, blunt teeth. Mandibles convex, with two large apical and two basal teeth and a few denticles along the intermediate border. Clypeus convex and carinate in the middle, its anterior border broadly and feebly excised in the middle and sinuate on each side. Frontal carinae very short, diverging; frontal area distinct, with a median carinula. Antennae slender, scapes reaching the middle of the head; funicular joints all longer than broad; club shorter than the remainder of the funiculus. Thorax shorter than the head, robust, through the pronotum nearly half as broad as the head, with very blunt humeri, convex and rounded in profile. Mesonotum sloping to the deep metanotal constriction with merely a trace of a transverse convexity in the middle. Propodeum broader than long, concave and sloping in the middle, in profile with the base distinctly shorter than the declivity; spines short, suberect, acute, less than half as long as the base and about half as long as their interval. Petiole about one and one-half times as long as broad, broader behind than in front, with concave sides; node transverse, its superior border sharp, feebly excised in the middle. Postpetiole broader than long, about two and one-half times as broad as the petiole, its sides produced as short, acute, slightly backwardly directed spines, its ventral surface with a small, acute tooth. Gaster smaller than the head, subcircular or very broadly elliptical, somewhat flattened above. Legs with moderately thickened femora.

Overall shining throughout; mandibles coarsely striate, smooth and coarsely punctate in the middle. Clypeus longitudinally rugulose, less distinctly in the middle than on the sides. Head rather finely and sharply longitudinally rugose, the rugae diverging on the front and continued to the posterior corners, where they meet the also slightly divergent rugae between the frontal carinae and the eyes. The interrugal spaces are loosely reticulate. There are no transverse rugae on the occiput but only a finer continuation of the more anterior sculpture. Thorax, petiole, and postpetiole indistinctly and loosely punctate rugulose, the prothorax transversely; propodeum with fine, dense but shallow punctures, so that the surface is more opaque, Gaster with fine, sparse, piligerous punctures. Hairs yellowish, partly coarse, sparse, uneven and suberect and partly short, much more abundant, softer and appressed or subappressed like long, coarse pubescence. Legs with numerous short, oblique hairs; scapes with a few longer spattered and coarser hairs.
Colour dark ferruginous red; mandibles, sides and border of clypeus, and frontal carinae, blackish; petiole, postpetiole, and gaster, except more or less of the base of the first segment, dark brown or blackish. Legs a little paler than the thorax.

MINOR - length 2.7 to 3 mm. Head subrectangular, as broad in front as behind, with straight, subparallel sides, rounded posterior corners and nearly straight posterior border. Eyes convex, at the middle of the sides. Mandibles rather large, deflected at the tip, with denticulate apical borders and two larger terminal teeth. Clypeus distinctly carinate, with the anterior border very feebly sinuate in the middle. Antennal scapes extending one-third their length beyond the posterior corners of the head. Thorax similar to that of the soldier, but more slender, especially through the pronotum. Propodeal dorsum a little longer than the declivity; spines slender, acute, erect, about half as long as their interval. Petiole slender, twice as long as broad, scarcely broader behind than in front, with the sides only very faintly concave; node transverse, its border distinctly notched in the middle. Postpetiole twice as broad as the petiole, as long as broad, subglobose, not toothed on the ventral side. Gaster about as large as the head.
Shining; mandibles subopaque, finely striatopunctate. Sides of head delicately longitudinally rugulose and reticulate. Thorax, petiole, and postpetiole finely and densely punctate, opaque; upper surface of pronotum and postpetiole smooth and shining. Gaster and legs shining, sparsely punctate. Pilosity like that of the soldier but less abundant. Antennal scapes, like the legs, with numerous oblique hairs.
Colour brown; head darker above and behind; gaster, except the edges of the segments, middle portions of legs, fore coxae, and usually also the pronotum and upper surfaces of the petiolar nodes, darker than the posterior portion of the thorax.

The photomontage of a cotype minor of the type form is collated from The Smithsonian Institute images at http://ripley.si.edu/ent/nmnhtypedb/public/specimeninfopage.cfm?publicconsumption=1&typespecimenID=967.

The photomontage is of a damaged worker from Congo, Réserve de Lésio-Louna, S 03°20'12.0" E 015°28'43.6"; n sp 61; pitfall trap 20, t 1; 4-5.ii.2008; Village Mah; collected by Eric Zassi.

Other images can be seen in the folder at -

This ant is certainly very closely related to P. sculpturata Mayr and might be regarded as a subspecies, but it will fit neither Mayr's description of the typical form from South Africa nor Santschi's and Forel's descriptions of the various subspecies from East and West Africa. Mr. Lang's note shows that it is a harvester. "The nests were found on a dry hill at the post of Zambi in rocky soil". Mostly nocturnal, harvesting seeds about about 8 am, the majors carrying the seeds back to the nest (illustrated right and "click").