Solenopsis corticalis

These ants nest in logs, under logs, in stumps, in forest litter and in the soil. Two nests were in the abandoned mounds of Solenopsis geminata, one in the abandoned mound of Solenopsis invicta. Sexuals are found in nests in June. Solenopsis corticalis was collected via surface, subterranean and vegetational traps (Vienna sausage, tuna fish), pitfall traps in a primary crown area and an in open area in Mexico and in wet montane cloud forest and oak forest in Panama. This species was collected in litter from wet cloud forest in Costa Rica and dry shrubland in Mexico. Moreover, S. corticalis was collected in litter from oak ridge forest, wet mountain cloud forest litter, montane/hardwood forest, pine forest and subterranean baits in Panama. Solenopsis corticalis was also collected at 1300 m in Peru. (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 small and yellow to golden yellow with the minor funicular segment length less than 0.120 mm in length. The lateral teeth are well developed while the extralateral teeth are absent. The clypeal carinae are well defined. It is a moderately hairy species with small eyes of 3-5 ommatidia. The petiole is robust and much wider than the postpetiole viewed laterally. Queen - The queen is small (less than 4.00 mm Total Length) and golden brown in color. The head is quadrate, smooth and shiny. What is striking about the gyne is the well-defined clypeal carinae. The petiolar peduncle has a thin ventral flange. Male -. The male is small (less than 3.00 mm TL) and is concolorous dark brown. The head is smooth and shiny and the medial ocellus is small. The mesosoma is smooth and shiny, but thin striae cover the propodeum. The petiolar node is angulate and is lacking a tooth or flange ventrally.

Solenopsis corticalis is similar to Solenopsis zeteki, which is found in many of the same areas. If queens are available, the queen of the former can be separated from the queen of S. zeteki as the eye is small (maximum diameter about 0.16 mm and 0.18 mm respectively). If queen are not present, the clypeal teeth of the workers of Solenopsis corticalis are more developed than those of S. zeteki.

Solenopsis corticalis is similar to Solenopsis tenuis (their distributions overlap) as well, but the clypeal teeth are more developed than ''S. tenuis. Solenopsis tenuis'' can be distinguished by its darker brown color. If queen are available, the queen of S. corticalis is yellow to golden brown, while that of S. tenuis'' is dark brown.

Distribution
Mexico (Chiapas, Tabasco, Veracruz) south to Panama (Chiriqui), western Peru and southeastern Brazil, Caribbean Region (Puerto Rico and Cuba).

Distribution based on Regional Taxon Lists
Nearctic Region: United States. Neotropical Region: Brazil, Colombia, Costa Rica, Cuba , French Guiana, Greater Antilles, Guatemala, Guyana, Lesser Antilles, Mexico, Nicaragua, Panama, Peru , Puerto Rico, Suriname, United States Virgin Islands.



Biology
Deyrup, Davis and Cover (2000): This species appears to be a complex, and the distribution records are therefore not reliable. Solenopsis corticalis was first reported from Florida in 1988 (Deyrup et al.), but there are specimens from the southeast coast dating back to 1945 (Thompson 1989). It should have been found in Wilson's survey of the Florida Keys (1964) if it had been as abundant then as it is now. If this species continues to show obvious changes in range and abundance we will be even more inclined to consider it an exotic.

Nomenclature

 *  corticalis. Solenopsis corticalis Forel, 1881: 13 (w.q.) ANTILLES. Senior synonym of amazonensis, binotata, margotae, virgula: Pacheco & Mackay, 2013: 142. See also: Thompson, 1989: 281.
 * amazonensis. Solenopsis corticalis r. amazonensis Forel, 1904e: 680 (w.q.) PERU. Junior synonym of corticalis: Pacheco & Mackay, 2013: 142.
 * binotata. Solenopsis corticalis var. binotata Mann, 1920: 428 (w.) CUBA. Junior synonym of corticalis: Pacheco & Mackay, 2013: 142.
 * margotae. Solenopsis corticalis subsp. margotae Forel, 1908c: 364 (w.q.) BRAZIL. Junior synonym of corticalis: Pacheco & Mackay, 2013: 142.
 * virgula. Solenopsis corticalis var. virgula Forel, 1904d: 172 (w.) CUBA. Menozzi, 1929a: 2 (q.). Junior synonym of corticalis: Pacheco & Mackay, 2013: 142.

Worker
Pacheco and Mackay (2013) - Measurements (n=20). TL 1.02-1.56 (1.29); HL 0.300-0.420 (0.378); HW 0.276-0.348 (0.313); EL 0.030-0.048 (0.038); ED 0.024-0.030 (0.028); SL 0.222-0.294 (0.258); FSL 0.078-0.120 (0.102); CI 78.1-92.0 (82.9); SI 61.5-80.0 (68.4); PL 0.054-0.078 (0.066); PW 0.078-0.090 (0.085); PI 64.3-92.9 (77.1); PPL 0.066-0.096 (0.084); PPW 0.102-0.108 (0.105); PPI 64.7-88.9 (80.5); WL 0.240-0.330 (0.268); PSL 0.018-0.030 (0.025); PSW 0.018-0.030 (0.021).

Small, concolorous pale yellow to golden yellow; head subquadrate, longer than wide; lateral clypeal teeth angulate, extralateral teeth absent; clypeal carinae well defined; eye small, 3-5 ommatidia; scape does not reach posterior lateral comer of head; minor funicular segments 3 -8 short; pronotum and mesopleuron smooth and shiny, metapleuron horizontally striated; posterior propodeal margin rounded, propodeal spiracle small; petiole robust, wider than postpetiole viewed laterally; petiolar peduncle lacking tooth or flange ventrally.

Moderately hairy; erect and suberect hairs of various lengths covering all body surfaces; hairs on head short, longest 0.090 mm; hairs on petiole and postpetiole curve posteriorly.

Queen
Pacheco and Mackay (2013) - Measurements (n=6). TL 2.64-4.08 (3.34); HL 0.480-0.630 (0.560); HW 0.390-0.528 (0.453); EL 0.138-0.192 (0.167); ED 0.114-0.156 (0.137); MOL 0.042-0.066 (0.046); MOD 0.042-0.060 (0.055); SL 0.282-0.421 (0.357); FSL 0.120-0.210 (0.175); CI 76.5-83.8 (80.8); SI 58.8-66.8 (63.4); PSL 0.042-0.066 (0.057); PSW 0.030-0.054 (0.048); PL 0.102-0.132 (0.113); PW 0.156-0.240 (0.201); PI 50.0-65.4 (57.3); PPL 0.132-0.180 (0.157); PPW 0.150-0.264 (0.211); PPI 63.6-92.0 (76.8); WL 0.600-0.840 (0.715).

Medium sized, concolorous golden brown; head subquadrate, longer than wide, finely punctate, smooth and shiny between punctures; lateral clypeal teeth angulate, extralateral positions with bumps; clypeal carinae well defined; pronotum, mesopleuron smooth and shiny; metapleuron horizontally striated; posterior propodeal margin with slight angle; petiole wider than postpetiole viewed laterally; petiolar node forming rounded triangle, with thin flange ventrally; postpetiole globose, lacking tooth or flange ventrally.

Abundantly hairy; erect and suberect hairs cover all body surfaces; most hairs on mesosoma, petiole and postpetiole curve posteriorly.

Male
Pacheco and Mackay (2013) - Measurements (n=4). TL 2.40-2.76 (2.55); HL 0.378-0.390 (0.384); HW 0.390; EL 0.180; ED 0.150-0.156 (0.153); MOL 0.054-0.060 (0.057); MOD 0.066; SL 0.168-0.174 (0.169); FSL 0.720; CI 100-103 (102); SI 43.1-45.3 (44.1); PSL 0.054-0.065 (0.058); PSW 0.060; PL 0.078; PW 0.150-0.162 (0.159); PI 48.1-52.0 (49.1); PPL 0.150-0.156 (0.152); PPW 0.180; PPI 83.3-86.7 (84.2); WL 0.720.

Small, concolorous dark brown; head wider than long, without sculpturing; clypeus convex, lacking tooth or angles; eyes large; medial ocellus small; pronotum, mesopleuron smooth, shiny; propodeum finely striate; posterior propodeal margin rounded; petiole wider than postpetiole viewed laterally; petiolar node angulate, lacking tooth or flange ventrally; postpetiolar node rounded.

Abundantly hairy, long (0.015 mm) erect and suberect hairs cover all body surfaces; hairs on petiole and postpetiole curve posteriorly.

Type Material
Pacheco and Mackay (2013) - Antilles Is., St. Thomas, (lectotype worker, 5 paralectotype workers and paralectotype queen [here designated] ). Solenopsis corticalis virgula, Cuba, Coll Ballion, ex. coll Puls., Forel coll. (lectotype worker [here designated] and 1 paralectotype worker, MHNG). Solenopsis corticalis amazonensis, Peru, Cerro de Escaler, 1300m, Nov. 1902, Tillandria 6602, Forel Coll. (lectotype worker [here designated] and 5 paralectotype workers MHNG). Solenopsis corticalis margotae, Brazil, Sao Paolo, (v. Ihering), Forel coll. (lectotype worker [here designated], 2 paralectotype workers, 3 paralectotype queens MHNG).