Formica planipilis

These ants nest in the soil, usually with some thatching of pine needles, but may also be found nesting in rotten logs and stumps in rocky and gravely soils. Brood and reproductives were found in nests from late June to mid August. Workers forage up into the canopy of pine trees. (Mackay and Mackay 2002)

Identification
The tentorial pit of this species is shallow. The middle and hind tibiae have a double row of bristles on the flexor surface, but each is with few hairs (fewer than 10 hairs in each row). There are a few scattered hairs on the other surfaces of the tibiae. The head of the major is longer than broad; the erect hairs on the mesosoma are short and of about equal length. The hairs on the head are longer and sparser than those on the mesosoma. (Mackay and Mackay 2002)

Distribution
Canada, Alberta. United States: North Dakota, Utah, Colorado, Kansas, Nevada and New Mexico.

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

Habitat
In New Mexico (Mackay and Mackay 2002) - Grasslands, open forests, ponderosa pine forests, often found in riparian areas, popular-spruce forests, up to about 3000 meters elevation.

Nomenclature

 *  planipilis. Formica rufa subsp. planipilis Creighton, 1940a: 9, fig. 1 (w.) U.S.A. Cole, 1956f: 259 (q.). Subspecies of integroides: Creighton, 1950a: 490. Raised to species: Cole, 1956f: 259.