Solenopsis zeteki

Solenopsis zeteki nests in the ground, are found loose on vegetation and are collected in bait traps (surface, subterranean and vegetation Vienna sausage) and pitfall traps from 110-1000 m. In Panama, S. zeteki was taken from a colony nesting in a cauline swelling of Cordia alliodora (Wheeler 1942). In Puerto Rico, S. zeteki was collected in old termite galleries in a dead branch of Leucaena leucocephala (Snelling 2001). It occurs in arid shrubland in Mexico and Colombia. (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 - This species is pale yellow with the lateral clypeal teeth reduced to blunt angles and the extralateral teeth absent. The eyes are relatively large with the length greater than 0.030 mm. The minor funicular segments are short, typically less than 0.10 mm in total length. The propodeum, petiole and postpetiole are smooth and shiny lacking any sculpturing. Queen - The queen is small and pale yellow. The lateral clypeal teeth are not well developed and are present as blunt angles. The mesosomal sculpture is smooth and shiny. What is striking about this species is the large eye (0.192 mm length and 0.156 mm diameter) for such a small gyne and separates it from most other species of the molesta group.

The Solenopsis zeteki worker is similar to that of Solenopsis corticalis in coloration, the short minor funicular segments and weakly developed lateral clypeal teeth. However, the worker of S. zeteki is easily separated in having a much larger eye. If queens are available, the queen of S. zeteki is easily recognized as it has a large eye (0.192 mm maximum diameter), which covers about 1/2 of the side of the head, compared to the much smaller eye of the queen of S. corticalis.

The small lateral clypeal teeth could cause confusion of this species with Solenopsis azteca (especially in the Caribbean). However, S. zeteki can be distinguished from S. azteca as it has a longer scape and a triangular petiolar node (more robust and rounded in S. azteca).

This species is difficult to separate from Solenopsis pollux. It is usually slightly smaller, but can be approximately equal in size. The lateral clypeal teeth of S. pollux 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. Specimens from Colombia are somewhat intermediate between the two, in having small, extralateral teeth, but have much less developed lateral clypeal teeth and are considered to be S. zeteki.

The specimens from Mexico are nearly identical to those of the type series, except for being slightly darker in coloration and although no queens were collected, these workers will be considered to be S. zeteki.

Distribution
Mexico (Veracruz) south to Colombia, Puerto Rico (Mona Island) and Saint Croix.

Distribution based on Regional Taxon Lists
Neotropical Region: Anguilla, Barbados, Colombia, Costa Rica, Grenada, Mexico, Netherlands Antilles, Nicaragua, Panama, Puerto Rico , Saint Martin (French part), United States Virgin Islands.

Castes
Males have yet to be collected.

Nomenclature

 * . Solenopsis zeteki Wheeler, W.M. 1942: 204 (w.) PANAMA.
 * Type-material: lectotype worker (by designation of Pacheco & Mackay, 2013: 363), 19 paralectotype workers.
 * [Note: Pacheco & Mackay, 2013: 363, also designate 4 paralectotype queens, but this caste was not mentioned in the original description.]
 * Type-locality: lectotype Panama: Canal Zone, Chivachiva trail, nr Red Tank (no collector’s name, presumably W.M. Wheeler); paralectotypes with same data.
 * Type-depository: MCZC.
 * Status as species: Ettershank, 1966: 144; Kempf, 1972a: 241; Bolton, 1995b: 392; Pacheco & Mackay, 2013: 361 (redescription); Wetterer, et al. 2016: 18; Deyrup, 2017: 116; Fernández & Serna, 2019: 816.
 * Senior synonym of torresi: Pacheco & Mackay, 2013: 361.
 * Distribution: Anguilla, Barbados, Colombia, Costa Rica, Mexico, Nicaragua, Panama, St Martin, U.S.A.
 * torresi. Solenopsis torresi Snelling, R.R. 2001: 514, figs. 1-7 (w.q.m.) PUERTO RICO.
 * Type-material: holotype worker, paratype workers, paratype queens, paratype males (numbers not stated).
 * Type-locality: holotype Puerto Rico: Mona I., nr airstrip, 13.xi.1992, RRS 92-76 (R.R. Snelling & J.A. Torres); paratypes with same data, or dated 29.x.1991, RRS 91-34.
 * Type-depositories: LACM (holotype); AEPR, BMNH, LACM, MCZC, USNM, WEMC (paratypes).
 * Junior synonym of zeteki: Pacheco & Mackay, 2013: 361.

Worker
Pacheco and Mackay (2013) - Measurements (n=6). TL 1.20-1.38 (1.27); HL 0.360-0.390 (0.385); HW 0.282-0.300 (0.295); EL 0.036-0.042 (0.041); ED 0.030; SL 0.240-0.258 (0.245); FSL 0.084-0.090 (0.085); CI 72.3-83.3 (76.7); SI 61.5-71.7 (63.7); PL 0.054-0.060 (0.059); PW 0.072-0.084 (0.076); PI 71.4-83.3 (77.8); PPL 0.072-0.078 (0.077); PPW 0.078-0.102 (0.092); PPI 76.5-92.3 (84.2); WL 0.240; PSL 0.018-0.024 (0.023); PSW 0.018-0.024 (0.022).

Small, concolorous pale yellow, head quadrate, longer than wide, cephalic punctures fine; lateral clypeal processes reduced to blunt angles, space between angles wide at 0.060 mm in length; extralateral processes absent; clypeal carinae well defined; eyes relatively large, oval-shaped; scape reaches 2/3 length of head; minor funicular segments 3-8 shorter than 0.10 mm in total length; mesosomal sculpture smooth and shiny; propodeal spiracle small; posterior propodeal margin rounded; petiole wider than postpetiole viewed laterally; petiolar node triangular, peduncle lacking tooth or flange ventrally; postpetiolar node oval.

Moderately hairy, erect and suberect hairs of various lengths covering all body surfaces; long (0.120 mm) suberect hairs on pronotum and propodeum; hairs on petiole and postpetiole curve posteriorly.

Queen
Pacheco and Mackay (2013) - Measurements (n=2), TL 3.3-3.36; HL 0.480-0.492; HW 0.408; EL 0.192-0.252; ED 0.150-0.156; MOL 0.060-0.066; MOD 0.048-0.060; SL 0.330-0.336; FSL 0.174-0.234; CI 82.9-85.0; SI 68.3-68.8; PSL 0.048; PSW 0.036-0.042; PL 0.138-0.168; PW 0.180-0.192; PI 76.7-114.3; PPL 0.174-0.210; PPW 0.234-0.240; PPI 87.5-134.5; WL 0.660-1.008.

Small, concolorous yellow; head longer than wide, fine cephalic punctures; lateral clypeal processes blunt angles, extralateral processes absent; clypeal carinae weakly defined; scape long, reaching ¾ length of head; minor funicular segments 3-8 relatively long; eyes large; mesosoma smooth and shiny; posterior propodeal margin rounded; petiole wider than postpetiole viewed laterally; petiolar node rounded, peduncle lacking tooth or flange ventrally; postpetiolar node oval.

Hairy; numerous erect and suberect hairs of various lengths covering all body surfaces; most hairs on propodeum, petiole, postpetiole and gaster curve posteriorly.

Type Material
Pacheco and Mackay (2013) - Panama (lectotype worker, 19 paralectotype workers and 4 paralectotype queens [here designated], type # 26289 ). Solenopsis torresi, Puerto Rico, Mona Island, 29-x-1991, R. R. Snelling & J.A. Torres, 91-34, R.R. Snelling 2001 (2 paratype workers, 1 paratype queen ).

References based on Global Ant Biodiversity Informatics

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