Solenopsis carolinensis

Solenopsis carolinensis has been collected in underground nests, among other ant nests, in termite nests, as well as in the trunks of rotten trees in North Carolina (Forel, 1901a). Both workers and alate males and queens were collected by berlese extraction of hardwood leaf litter in Arkansas. Solenopsis carolinensis was collected under the bark of a dead tree and in a stump in Tennessee. Solenopsis carolinensis has also been collected by black light (July), in log litter and under rocks in various localities in Texas. Brood and sexuals were in nests in June. This species was collected in a Pinus taeda, mixed hardwood forest. Solenopsis carolinensis was also collected at 8500 ft. (about 2591 m) in Woodland Park Colorado. It is also found in grasslands and shrublands. (Pacheco and Mackay 2013)

Identification
A New World thief ant that is a member of the molesta species complex. (Key to New World Solenopsis Species Complexes)

Pacheco and Mackay (2013) – Worker - The workers are nearly always small and yellow, but can be brown. The lateral clypeal teeth are angulate with the extralateral teeth absent. The mesosoma is smooth and shiny. This species is abundantly hairy and hairs on the posterior tibia are usually suberect. Queen - The queen is yellow, with large eyes. The head is coarsely punctate. The ocelli are darkly pigmented. The petiolar peduncle has a well-developed flange. Male - The male is slightly bicolored with a brown head and gaster and yellowish mesosoma, petiole and postpetiole. The head is mostly smooth and shiny and the clypeus is lacking any tooth or bump. The petiolar peduncle has a small flange ventrally.

Solenopsis carolinensis is difficult to separate from Solenopsis zeteki. It is usually slightly larger to the latter, but they can be approximately equal in size. The lateral clypeal teeth of S. carolinensis are well developed and the extralateral processes are developed at least into an angle. The lateral teeth are usually absent in S. zeteki, but may be developed into small angles. The extralateral angles of S. zeteki are absent or developed into a wide, slightly expanded area. Moreover, these two species can be separated by geography as S. carolinensis is found in the USA and S. zeteki is from Central and South America.

Solenopsis carolinensis could be confused with Solenopsis texana and with Solenopsis abdita. The workers of these two species have appressed hairs present on the posterior tibiae, whereas S. carolinensis has suberect pilosity. When queens are available, S. carolinensis, is easily distinguished by the large diameter of the eye. Queens and workers can be separated from those of S. abdita by the longer scapes (scape length of two type workers 0.240 and 0.279 mm, respectively) and the relatively narrower petiole (petiolar width of two type workers 0.083 and 0.094 mm, respectively).

Distribution
United States: Arkansas, Maryland, New Jersey, North Carolina, Tennessee, Texas, Virginia.

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

Fungi
This species is a host for the endoparastic fungus Myrmicinosporidium durum (Espadaler & Santamaria, 2012).

Nomenclature

 *  carolinensis. Solenopsis texana r. carolinensis Forel, 1901e: 345 (w.q.m.) U.S.A. Combination in S. (Diplorhoptrum): Creighton, 1950a: 236. Raised to species: Creighton, 1950a: 236. See also: Thompson & Johnson, 1989: 698.
 * castanea. Solenopsis molesta var. castanea Wheeler, W.M. 1908e: 430 (w.) U.S.A. Junior synonym of truncorum: Creighton, 1950a: 239; of carolinensis: Pacheco & Mackay, 2013: 127.
 * truncorum. Solenopsis texana r. truncorum Forel, 1901e: 346 (w.q.) U.S.A. Raised to species and senior synonym of castanea: Creighton, 1950a: 239. Junior synonym of carolinensis: Pacheco & Mackay, 2013: 127. See also: Thompson & Johnson, 1989: 697.

Worker
Pacheco and Mackay (2013) - Measurements (n=6). TL 1.32-1.48 (1.42); HL 0.402-0.420 (0.412); HW 0.324-0.360 (0.337); EL 0.036-0.042 (0.041); ED 0.030-0.036 (0.031); SL 0.270-0.300 (0.279); FSL 0.102-0.120 (0.108); CI 78.6-85.7 (81.8); SI 64.3-71.4 (67.7); PL 0.060-0.072 (0.065); PW 0.090-0.102 (0.094); PI 58.8-75.0 (69.4); PPL 0.066-0.084 (0.076); PPW 0.120-0.126 (0.122); PPI 55.0-70.0 (62.3); WL 0.300-0.330 (0.305); PSL 0.024-0.030 (0.029); PSW 0.024.

Small, concolorous yellow; head subquadrate, longer than wide, posterior border straight; lateral clypeal teeth angulate, extralateral teeth absent; clypeal carinae well defined; scape reaches 3/4 length of head; minor funicular segments 3-8 short; eyes small, 3-5 ommatidia; mesosoma smooth and shiny; metapleuron with faint horizontal striae; posterior propodeal margin rounded; petiole wider than postpetiole viewed laterally; petiolar node rounded, subtriangular, with tooth ventrally; postpetiolar node rounded, globose, sculpture of petiole and postpetiole smooth and shiny.

Abundantly hairy; erect and suberect hairs of various lengths on all body surfaces; hairs on posterior tibia usually at least suberect.

Queen
Pacheco and Mackay (2013) - Measurements (n=2). TL 4.08-4.20 (4.14); HL 0.648; HW 0.600; EL 0.240; ED 0.180-0.192 (0.186); MOL 0.078-0.090 (0.084); MOD 0.084-0.096 (0.090); SL 0.450-0.462 (0.456); FSL 0.222-0.240 (0.231); CI 92.6; SI 69.4-71.3 (70.4); PSL 0.066; PSW 0.048-0.060 (0.054); PL 0.132; PW 0.246-0.270 (0.258); PI 48.9-53.7 (51.3); PPL 0.198; PPW 0.282-0.288 (0.285); PPI 68.8-70.2 (69.5); WL 0.900.

Moderately large; concolorous yellow; head sub quadrate, longer than wide, coarsely punctate, posterior margin straight; lateral clypeal teeth angulate, extralateral teeth absent; clypeal carinae poorly defined; frontal lobes vertically striated; eye black, large; ocelli darkly pigmented, medial ocellus large; pronotum coarsely punctate, smooth and shiny between punctures, mesopleuron without sculpturing, lower metapleuron with horizontal striae; petiole wider than postpetiole viewed laterally; petiolar peduncle with well-developed flange ventrally. Abundantly hairy; erect and suberect hairs of various lengths covering all body surfaces; most hairs on petiole and postpetiole curve posteriorly.

Male
Pacheco and Mackay (2013) - Measurements (n=4). TL 2.88-3.00 (2.91); HL 0.432-0.450 (0.441); HW 0.402-0.480 (0.446); EL 0.282-0.300 (0.291); ED 0.240; MOL 0.084-0.090 (0.087); MOD 0.132-0.150 (0.141); SL 0.144-0.168 (0.155); FSL 0.900-0.960 (0.945); CI 93.1-107 (101); SI 33.3-37.3 (35.0); PSL 0.072; PSW 0.060-0.066 (0.064); PL 0.138-0.144 (0.139); PW 0.198-0.216 (0.209); PI 63.9-69.7 (66.9); PPL 0.144-0.162 (0.153); PPW 0.228; PPI 63.2-71.1 (67.1); WL 0.720-0.840 (0.780).

Bicolored, brown head and gaster, yellow mesosoma, petiole and postpetiole, antennae yellow; head wider than long, smooth, shiny; clypeus convex, lacking tooth or bump; frontal lobes widely separated, 0.096 mm in greatest width; mesosoma smooth, shiny; petiole wider than postpetiole viewed laterally; petiolar peduncle with small flange ventrally; postpetiole wider than petiole viewed dorsally, lacking tooth or flange ventrally.

Abundantly hairy, with erect and suberect hairs of various lengths covering all body surfaces; most hairs on petiole and postpetiole curve posteriorly.

Type Material
Pacheco and Mackay (2013) - North Carolina, Faisons, (lectotype worker and 5 paralectotype workers [here designated], cotype #201786 ). Solenopsis texanus truncorum, (lectotype queen, 1 paralectotype queen, 6 paralectotype workers [here designated] MHNG). Solenopsis texana truncorum, North Carolina, Faisons du tronc 28.VII.