Solenopsis molesta

This is a common, widely distributed species. Nests are found in the soil (often under stones) and often adjacent to the nests of other species, where it steals food or brood from its host. Reproductives and brood are present throughout the summer. This is also a household pest, although it may not be noticed due to its small size. It hollows out seeds, thus destroying seed in beds. Colonies contain up to a few thousand workers. Sexuals are found in nests from July to October. Nuptial flights occur from late July to early fall, individuals mate in the air. These ants are predaceous, but are also omnivorous (feeding on seeds) and eat dead insects. They also tend Homoptera. (Mackay and Mackay 2002)

Identification
Small ants, typically clear yellow with small punctures on the dorsum of the head that are only slightly larger in diameter than the hairs that arise from them. (Mackay and Mackay 2002)

Distribution
A wide range that includes southern areas of Canada, most of the continental US and northern Mexico.

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

Biology
Solenopsis molesta has been collected in the nests of ''Myrmica americana, Manica invidia, Pogonomyrmex occidentalis, Po. montanus, Messor lobognathus, Monomorium minimum, Pheidole bicarinata, Ph. pilifera, Dorymyrmex insanus, Camponotus vicinus, Lasius crypticus, L. neoniger, L. sitiens, L. umbratus, Acanthomyops claviger, A. interjectus, A. murphyi, Formica argentea, F. neogagates, F. limata, F. rubicunda, F. bradleyi, F. altipetens, and F. fusca''. (Mackay and Mackay 2002)

Nomenclature

 *  molesta. Myrmica molesta Say, 1836: 293 (q.) U.S.A. Wheeler, G.C. & Wheeler, J. 1955c: 134 (l.); Petralia & Vinson, 1980: 383 (l.); Crozier, 1970: 116 (k.). Combination in Solenopsis: Mayr, 1863: 407; in S. (Diplorhoptrum): Creighton, 1950a: 237. Senior synonym of debilis, exigua, minuta: Emery, 1895c: 277; Emery, 1896g: 85.
 * minuta. Myrmica minuta Say, 1836: 294 (w.) U.S.A. Junior synonym of molesta: Emery, 1895c: 277.
 * exigua. Myrmica (Tetramorium) exigua Buckley, 1867: 342 (w.q.) U.S.A. Junior synonym of molesta: Emery, 1895c: 277. See also: Wheeler, W.M. 1902f: 28.
 * debilis. Solenopsis debilis Mayr, 1886d: 461 (w.q.m.) U.S.A. Junior synonym of molesta: Emery, 1895c: 277; Emery, 1896g: 85.

Worker
Pacheco and Mackay (2013) - Measurements (n=6). TL 1.38-1.62 (1.50); HL 0.420-0.510 (0.457); HW 0.360-0.432 (0.386); EL 0.036-0.042 (0.040); ED 0.030-0.036 (0.032); SL 0.282-0.348 (0.317); FSL 0.132-0.156 (0.141); CI 81.1-87.8 (84.5); SI 64.7-72.9 (69.4); PL 0.072-0.096 (0.083); PW 0.120-0.156 (0.126); PI 57.7-80.0 (66.3); PPL 0.102-0.120 (0.108); PPW 0.120-0.162 (0.135); PPI 74.1-85.7 (80.4); WL 0.300-0.342 (0.325); PSL 0.030-0.036 (0.032); PSW 0.030.

Small; concolorous yellow to pale brown; head longer than wide, sides nearly straight, finely punctate; lateral clypeal teeth well developed, extralateral teeth absent; clypeal carinae well defined; scape long, nearly reaching posterior lateral corner of head; minor funicular segments moderately long; eye small, 3-5 ommatidia; pronotum finely punctate, smooth and shiny between punctures; mesopleuron smooth and shiny; notopropodeal suture well depressed, notch-shaped, groove breaks sculpture of mesosoma; posterior border of propodeum rounded; propodeal spiracle small, round; metapleuron horizontally striated; petiole wider than postpetiole viewed laterally; petiolar peduncle with minute angle ventrally; postpetiolar node semicircular viewed laterally, lacking tooth or flange ventrally.

Abundantly hairy, pilosity yellow; erect and suberect hairs covering all body surfaces; scape with numerous appressed hairs; dorsum of mesosoma with hairs of various lengths (0.060-0.120 mm); hairs on petiole, postpetiole and gaster curve posteriorly.