Formica ferocula

The type colony and several other colonies of the same species were found nesting in dry, open fields in crater nests 3-4 inches in diameter about the roots of Erigeron canadense and other weeds. (Wheeler 1913)

Identification
The species is evidently allied to Formica comata, Formica criniventris, Formica ciliata, and Formica oreas, but differs from all of these forms in the peculiar shape of the petiole and the arrangement of the hairs. (Wheeler 1913)

Distribution based on Regional Taxon Lists
Nearctic Region: United States.

Nomenclature

 *  ferocula. Formica ferocula Wheeler, W.M. 1913f: 461 (w.) U.S.A.

Worker
Length 3.5-6 mm.

Head, excluding the mandibles, as broad as long, broader behind than in front, with feebly excised posterior border and very slightly convex sides. Mandibles 8-toothed. Clypeus convex, carinate its entire length, with broadly rounded anterior border, but slightly or not at all produced in the middle. Frontal area triangular, as long as broad. Frontal carinae short, diverging. Antennae slender, four basal funicular joints longer and more slender than the penultimate joints. Palpi short. Pro- and mesonotum not very convex, mesoepinotal constriction not very deep, epinotum with subequal base and declivity, the former feebly convex, the latter distinctly concave. Petiole narrow and very low, its anterior surface very convex, its posterior surface flattened, its border very blunt and when seen from behind, evenly rounded and entire, not produced upward in the middle. Legs rather long.

Opaque, finely shagreened; mandibles shining, rather superficially striatopunctate; frontal area smooth and shining, clypeus also more shining than the posterior part of the head.

Hairs and pubescence golden yellow; the former abundant on the clypeus and mandibles, absent on the remaining portions of the head; dense and erect on the pronotum, epinotum, and petiole, absent on the mesonotum, except at the posterior border. On the gaster the erect hairs are short, obtuse, and rather abundant. Eyes hairless. Pubescence long and rather dense on the head and thorax, scarcely denser on the gaster and not concealing the ground color. Pubescence on the legs long and somewhat oblique on the flexor surfaces of the tibiae.

Bright yellowish red; mandibles, antennal funiculi towards their tips, and the legs in some specimens, darker. Gaster dark brown, with the anal region and a spot at the base of the first segment red. Very small workers have the upper surface of the head, thorax, and petiole infuscated and the legs darker.

References based on Global Ant Biodiversity Informatics

 * Carroll T. M. 2011. The ants of Indiana (Hymenoptera: Formicidae). Master's Thesis Purdue university, 385 pages.
 * Wheeler W. M. 1913. A revision of the ants of the genus Formica (Linné) Mayr. Bulletin of the Museum of Comparative Zoology 53: 379-565.