Crematogaster coarctata mormonum

Crematogaster mormonum nest in rotten limbs in termite holes, as well as soil adjacent to the wood. Brood occurred in nests in April, sexuals in August. (Mackay and Mackay 2002)

Identification
The workers can be recognized as the pronotum is nearly smooth and shining, the upper half of the mesopleuron has well defined rugae or striae, the lower half is punctate with the punctures lining up into striae, the side of the propodeum has striae with the background shining. The dorsum of the mesosoma has poorly defined striae with the background smooth and shining. The head and the posterior face of the propodeum are predominantly smooth and shining. The pronotum has several erect hairs (approximately 3) on each pronotal shoulder. (Mackay and Mackay 2002)

Distribution
Southern California, Idaho, Utah, Nevada, New Mexico and Mexico.

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



Biology
Nevada, Wheeler and Wheeler (1986) - We have 107 records from 86 localities which are widely distributed, except absent from the northeastern quarter of the state; 3,800-8,000 ft.; median 5,800 ft. Thirty-six records were in the Cool Desert (14 in Sarcobatus Subclimax, 5 in Atriplex Subclimax, and 1 in cottonwood riparian), 1 from the Hot Desert, and 34 from the Pinyon-Juniper Biome. Forty-eight nests were under stones, 5 were under wood, 1 was in a stump, 1 was in exposed soil surmounted by a crater, and 1 was in soil at the base of an Atriplex shrub. In 16 records workers were taken at the base of shrubs (1 Artemisia, 4 Atriplex, 1 Coleogyne, 3 Ephedra, 7 Sarcobatus), where Homoptera were tended, but no nests were found.

A teneral Anthicus punctulatus LeC. (Coleoptera: Anthicidae; det. F. Werner) was taken in the nest at Denio (Humboldt Co.) 4,300 ft. The following myrmecophilous mealybugs (Homoptera: Pseudococcidae; det. D.R. Miller) were tended by C. mormonum: Puto atriplicis McKenzie on Atriplex confertifolia, 10 mi. NE Stillwater (1020N- 32) (Churchill Co.) 3,900 ft.; Phenococcus solenopsis Tinsley on Atriplex confertifolia, 41 mi. E Lovelock in Pleasant Valley (pershing Co.) 3,800 ft. A colony at Dyer (Esmeralda Co.) 5,100 ft. was tending both Aphis bonnevillensis Knowlton (Homoptera: Aphididae; det. L.M. Russell) and Orthezia sarcobati Morrison (Homoptera: Ortheziidae; det. D.R. Miller) at the base of Sarcobatus vermiculatus.

Nomenclature

 *  mormonum. Crematogaster coarctata var. mormonum Wheeler, W.M. 1919g: 111 (w.) U.S.A. [First available use of Crematogaster lineolata subsp. coarctata var. mormonum Emery, 1895c: 284; unavailable name.] Combination in C. (Acrocoelia): Emery, 1922e: 141; in C. (Crematogaster): Buren, 1968b: 94. Raised to species: Creighton, 1950a: 215.