Solenopsis franki

Specimens from Risaralda (Columbia) were collected in dry forest at 950 m as well as in leaf litter from a coffee plantation at 1405m. A specimen from Valle del Cauca (Columbia) was collected in a pitfall trap in wet rainforest, with dark clay soils. (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 is a concolorous golden-yellow species. The lateral clypeal teeth are present, but not well developed. The extralateral teeth are present as bumps. The clypeus is slightly concave medially. The head is longer than wide and is nearly rectangular, with the posterior border nearly straight. The eyes are typically black and contain about 3-5 ommatidia. The scape is long and extends nearly the length of the head. The petiole is thicker than the postpetiole when viewed in profile. Queen - The queen is small and golden yellow in color. The clypeus is concave medially with the lateral teeth well developed, while the extralateral teeth are present as bumps. What is striking about the queen is that the three ocelli are clear but very small (smaller than the propodeal spiracle). There are small, fine punctures present on the head, the pronotum and the first tergum of the gaster. The posterior propodeal margin is slightly angled. There are vertical striae present on the lower half of the propodeum which end before they reach the spiracle. The postpetiole is much smaller than the petiole when viewed in profile, but is much wider when viewed from above.

This workers of this species are similar to those of Solenopsis hayemi (distributions overlap) but can be separated by size. Solenopsis hayemi is consistently larger in size (2.00-2.10 mm) compared to S. franki (1.47-1.68 mm). The distinguishing feature between the two is that S. franki does not have such a wide petiole viewed laterally when compared to that of S. hayemi. Solenopsis franki is similar to Solenopsis decipiens (South America) but can be separated as S. decipiens has a kidney-shaped eye, less developed clypeal carinae and a less robust petiole when viewed laterally.

Distribution based on Regional Taxon Lists
Neotropical Region: Argentina, Brazil, Colombia, Guyana, Paraguay.

Castes
Males have yet to be collected.

Nomenclature

 * . Solenopsis franki Forel, 1908c: 364 (w.) BRAZIL (São Paulo).
 * Type-material: lectotype worker (by designation of Pacheco & Mackay, 2013: 156), 3 paralectotype workers.
 * [Note: Pacheco & Mackay also nominate a paralectotype queen, but this caste is not mentioned in the original description.]
 * Type-locality: lectotype Brazil: São Paulo (von Ihering); paralectotypes with same data.
 * Type-depository: MHNG.
 * Forel, 1909a: 259 (q.).
 * Status as species: Forel, 1909a: 259; Luederwaldt, 1918: 42; Emery, 1922e: 199; Borgmeier, 1927c: 104; Ettershank, 1966: 140; Kempf, 1972a: 235; Bolton, 1995b: 387; Wild, 2007b: 36; Pacheco & Mackay, 2013: 155 (redescription); Fernández & Serna, 2019: 816.
 * Distribution: Brazil, Colombia, Guyana, Paraguay.

Worker
Pacheco and Mackay (2013) - Measurements (n=7). TL 1.47-1.68 (1.55); HL 0.426-0.468 (0.456); HW 0.372-0.402 (0.384); EL 0.036-0.048 (0.044); ED 0.030-0.036 (0.032); SL 0.306-0.330 (0.321); FSL 0.132-0.144 (0.137); CI 79.5-90.1 (84.3); SI 66.7-73.3 (70.4); PL 0.096-0.108 (0.100); PW 0.096-0.114 (0.105); PI 89.5-100 (96.2); PPL 0.096-0.114 (0.103); PPW 0.126-0.138 (0.130); PPI 72.7-90.5 (79.3); WL 0.360-0.390 (0.364); PSL 0.030-0.042 (0.036); PSW 0.030.

Small, concolorous golden yellow; head rectangular, longer than wide, posterior border straight; lateral clypeal teeth angulate, extralateral teeth are bumps; anterior clypeal margin concave; clypeal carinae well developed; eyes contain 3-5 ommatidia; scape long, extends nearly to posterior border of head; notopropodeal suture well depressed, groove breaks sculpture of mesosoma; petiole thicker than postpetiole viewed laterally.

Moderately hairy, with erect and suberect hair of various lengths present on all body surfaces; mesosoma, petiole, postpetiole and gaster with erect and suberect hairs; petiole and postpetiole with hairs that curve posteriorly.

Queen
Pacheco and Mackay (2013) - Measurements (n=1). TL 3.00; HL 0.546; HW 0.510; EL 0.150; ED 0.120; MOL 0.048; MOD 0.054; SL 0.348; FSL 0.162; CI 93.4; SI 63.7; PSL 0.050; PSW 0.060; PL 0.120; PW 0.210; PI 57.1; PPL 0.120; PPW 0.138; PPI 86.9; WL 0.450.

Small, concolorous golden-yellow; head rectangular, longer than wide, cephalic punctures fine; anterior clypeal margin concave with space between lateral teeth wide at 0.108 mm; lateral clypeal teeth well developed, extralateral teeth are bumps; clypeal carinae well developed; eyes black, moderately large; ocelli small, clear; scape long, nearly reaching posterior border of head; pronotum finely punctate; mesopleuron smooth and shiny; metapleuron finely striate; posterior propodeal margin angulate; petiole wider than postpetiole viewed laterally; petiole and postpetiole striolate; first tergum of gaster finely punctate.

Abundantly hairy on all body surfaces, with erect and suberect hairs of various lengths; nearly all punctures have a suberect hair.

Type Material
Pacheco and Mackay (2013) - Brazil, Sao Paulo (v. Ihering) (lectotype worker [here designated], 3 paralectotype workers and 1 paralectotype queen ).

References based on Global Ant Biodiversity Informatics

 * Fernández, F. and S. Sendoya. 2004. Lista de las hormigas neotropicales. Biota Colombiana Volume 5, Number 1.
 * Forel A. 1908. Ameisen aus Sao Paulo (Brasilien), Paraguay etc. gesammelt von Prof. Herm. v. Ihering, Dr. Lutz, Dr. Fiebrig, etc. Verhandlungen der Kaiserlich-Königlichen Zoologisch-Botanischen Gesellschaft in Wien 58: 340-418.
 * Forel A. 1909. Ameisen aus Guatemala usw., Paraguay und Argentinien (Hym.). Deutsche Entomologische Zeitschrift 1909: 239-269.
 * Kempf, W.W. 1972. Catalago abreviado das formigas da regiao Neotropical (Hym. Formicidae) Studia Entomologica 15(1-4).
 * Pacheco J. A., and W. P. Mackay. 2013. The systematics and biology of the New World thief ants of the genus Solenopsis (Hymenoptera: Formicidae). Lewiston, New York: Edwin Mellen Press, 501 pp.
 * Ulyssea M. A., C. R. F. Brandao. 2013. Catalogue of Dacetini and Solenopsidini ant type specimens (Hymenoptera, Formicidae, Myrmicinae) deposited in the Museu de Zoologia da Universidade de Sao Paulo, Brazil. Papies Avulsos de Zoologia 53(14): 187-209.
 * Wild, A. L. "A catalogue of the ants of Paraguay (Hymenoptera: Formicidae)." Zootaxa 1622 (2007): 1-55.