Aphaenogaster uinta

A Great Basin and Colorado Plateau ant that favors arid areas but can be found in cool desert, pinyon-juniper and coniferous forest habitats. It can nest under wood or stones but will also build in exposed situations and create nest openings with 6 to 8 cm craters. It forages nocturnally and nests may contain several hundred workers.

These ants live between thin layer of limestone in arid areas (DeMarco, 2015).

Identification
Small to medium-sized. Bicolored: head and thorax yellowish red, gaster very dusky gray varying to head and thorax red, gaster very dusky red. In the field and to the unaided eye the gaster appears black; hence this species exhibits the coloration characteristic of several species of desert ants (Wheeler & Wheeler, 1973:12). Head and thorax partially shining, gaster strongly shining. (Wheeler & Wheeler, 1986)

Aphaenogaster uinta is one of several Aphaenogaster species with a lighter head and mesosoma, and darker gaster. They have large eyes, very short propodeal spines and scapes that extend just beyond the occiput of the head. (DeMarco, 2015)

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

Colorado Notes
So far as Colorado is concerned, this species is exceedingly rare. The sole record I possess for it was obtained from Dr. Creighton, who collected it a long time ago in the southwestern portion of the state. According to Creighton (1950), the ant is a Great Basin insect and it is said to thrive in areas of marked aridity. From these facts, we may assume that in the Mesa Verde area, Aphaenogaster uinta was, without much doubt, nesting in the dry, hot part of the park rather than in a Transition Zone locality. (Gregg, 1963)

Nevada Notes
In Nevada it is widely scattered throughout the state; 4,500-8,000 ft. We have 37 records from 31 localities. Eight records were from the Cool Desert (2 from disturbed habitats), 15 from the Pinyon-Juniper Biome, 1 from the Coniferous Forest Biome, and 1 from a building. Fifteen nests were under stones, 1 under a log; 2 nests were exposed with craters 6 and 8 cm in diameter. A mating flight occurred in Tonopah on 13 July. The myrmecophile Pilopius ocularis Casey (Coleoptera: Pselaphidae; det. R.R. Snelling) was found with this ant at Panaca Summit, Lincoln Co. 6,700 ft. (Wheeler & Wheeler, 1986)

Nomenclature

 *  uinta. Aphaenogaster uinta Wheeler, W.M. 1917a: 517 (w.q.m.) U.S.A. Combination in Aphaenogaster (Attomyrma): Emery, 1921f: 60.

Description
Wheeler (1917) likely choose this name based on the type specimens being collected where the Uinta Mountains loomed on the eastern horizon. As stated in the original description: “Described from seventeen workers, one female and one male taken by Dr. R.V. Chamberlin at East Mill Creek, Salt Lake County, Utah.”
 * Etymology