Solenopsis terricola

Solenopsis terricola was collected in Berlese extractions of litter from transitional dry tropical forest, mountain hardwood, bamboo/cloud, wet cloud, wet montane forests and in cloud forest transition litter in Costa Rica at 600-4000 m. This species was collected at 950 m in Riparian oak forest litter in Panama at 950 m.

Identification
A New World thief ant that is a member of the brevicornis species complex

Pacheco and Mackay (2013) – Worker - This is a small (1.23 mm TL), bicolored (concolorous pale brown in the Caribbean) species. The body is dark brown to black, strongly contrasting with the yellow appendages. The head is elongated with straight sides. This species has moderately small eyes, but with at least five ommatidia The mesopleuron and metapleuron are punctated. The petiole and postpetiole are at least partially punctated or with roughened sculpturing. Queen - The queen is small and medium brown in color with lighter colored appendages. Vertical striae extend from the frontal lobes up the dorsum of the head to the medial ocellus. The propodeum, petiole and postpetiole are covered in roughened sculpturing.

Solenopsis terricola is similar to Solenopsis azteca (Honduras to Venezuela, Caribbean) and Solenopsis brevicornis (Mexico to Brazil). It can be distinguished from S. azteca by the punctures on the side of the mesopleuron (completely smooth and polished in S. azteca or with weak sculpture along the lower, anterior border of the mesopleuron). Solenopsis terricola is dark, mahogany brown, with yellow antennae and legs (in Central America), which separates it from the concolorous brown S. brevicornis. It is concolorous brown in the Caribbean (Santa Lucia and Dominica), similar to the color of S. brevicornis, which has not been collected on these islands. Both S. terricola and S. brevicornis have the mesopleuron at least partially punctated, but the side of the petiole of S. terricola is mostly smooth and glossy (except basally) and is completely punctate in S. brevicornis.

Solenopsis terricola has striated frontal lobes, a trait absent in both S. azteca and S. brevicornis. Moreover, the apex of the petiolar node is rounded in S. terricola, but angulate with S. brevicornis.

Keys

 * Key to New World Solenopsis Species Complexes
 * Key to Solenopsis brevicornis species complex / Clave para las obreras del complejo brevicornis

Distribution based on Regional Taxon Lists
Neotropical Region: Costa Rica, Dominica, Dominican Republic, Guatemala, Mexico, Panama, Saint Lucia.

Nomenclature

 * . Solenopsis terricola Menozzi, 1931b: 267, fig. 5 (w.q.) COSTA RICA.
 * Type-material: lectotype worker (by designation of Pacheco & Mackay, 2013: 328), 2 paralectotype workers.
 * Type-locality: lectotype Costa Rica: Puente de Las Mulas (F,I, Tristan); paralectotypes with same data.
 * [Note: original description also includes a single syntype queen.]
 * Type-depository: IEUB.
 * Status as species: Ettershank, 1966: 144; Kempf, 1972a: 240; Bolton, 1995b: 391; Branstetter & Sáenz, 2012: 261; Pacheco & Mackay, 2013: 326 (redescription); Deyrup, 2017: 113; Lubertazzi, 2019: 175.
 * Distribution: Costa Rica, Dominica, Dominican Republic, Guatemala, Panama, St Lucia, U.S.A.

Worker
Pacheco and Mackay (2013) - Measurements (n=5). TL 1.20-1.32 (1.23); HL 0.360-0.408 (0.384); HW 0.300-0.348 (0.320); EL 0.042-0.048 (0.046); ED 0.036; SL 0.204-0.210 (0.206); FSL 0.060-0.078 (0.072); CI 78.1-89.2 (83.4); SI 50.0-56.7 (53.8); PL 0.060-0.066 (0.064); PW 0.084-0.090 (0.088); PI 66.7-78.6 (72.8); PPL 0.084; PPW 0.108-0.120 (0.118); PPI 70.0-77.8 (71.6); WL 0.270-0.300 (0.282); PSL 0.030-0.036 (0.031); PSW 0.030.

Small, bicolored, head, mesosoma and gaster dark brown to black, legs and antennae yellow; head elongated, sides of head straight, posterior margin straight; eyes black with at least five ommatidia; anterior clypeal margin concave between teeth, lateral clypeal teeth poorly developed, medial tooth and extralateral teeth absent; frontal lobes vertically striated (often difficult to see); scape short, extends slightly more than half-length of head to posterior lateral corner; mesopleuron and metapleuron punctate; petiole wider than postpetiole viewed laterally; petiole and postpetiole partially punctate, both lacking tooth or flange ventrally.

Short (~0.020 mm), suberect and long (0.050 mm), erect hairs sparse on head; antennae hairy; scape has few suberect hairs; mesosoma, petiole and postpetiole with scattered suberect hairs; head with several small punctures, about equal in diameter to hairs that originate from them, surfaces between punctures smooth and shiny.

Queen
Pacheco and Mackay (2013) - Measurements (n=5). TL 2.28-3.18 (2.65); HL 0.438-0.558 (0.481); HW 0.390-0.480 (0.418); EL 0.132-0.162 (0.150); ED 0.102-0.132 (0.113); MOL 0.036-0.042 (0.041); MOD 0.042-0.048 (0.047); SL 0.300-0.342 (0.308); FSL 0.120-0.168 (0.145); CI 85.5-89.0 (86.9); SI 53.8-68.5 (64.5); PSL 0.042-0.054 (0.052); PSW 0.036-0.054 (0.050); PL 0.096-0.132 (0.107); PW 0.180-0.228 (0.189); PI 53.3-57.9 (56.2); PPL 0.138-0.180 (0.154); PPW 0.198-0.240 (0.212); PPI 65.7-75.8 (72.3); WL 0.570-0.720 (0.606).

Small, concolorous medium brown with yellowish appendages; head longer than wide, coarsely punctate; lateral clypeal teeth angulate, wide space between tips of teeth (0.096 nun), extralateral teeth absent; clypeal carinae well defined; frontal lobes vertically striated, striae extend nearly to level of medial ocellus; medial ocellus small; scape short; eyes large, extend 0.060 nun past lateral margin of head; pronotum and mesopleuron smooth and shiny; posterior propodeal margin rounded; propodeal spiracle small, round; metapleuron with roughened sculpturing; petiole wider than postpetiole viewed laterally; petiolar node with roughened sculpturing, peduncle lacking tooth or flange ventrally; postpetiolar node with roughened sculpturing lacking tooth or flange ventrally.

Abundantly hairy, pilosity yellow; erect and suberect hairs on all body surfaces; hairs on pronotum unifonn in size (many 0.120 mm in length); hairs on petiole, postpetiole and first gastral tergum curve posteriorly.

Type Material
Costa Rica, Puente de las Mulas (lectotype worker and 2 paralectotype workers [here designated] ).

References based on Global Ant Biodiversity Informatics

 * Castano-Meneses, G., M. Vasquez-Bolanos, J. L. Navarrete-Heredia, G. A. Quiroz-Rocha, and I. Alcala-Martinez. 2015. Avances de Formicidae de Mexico. Universidad Nacional Autonoma de Mexico.
 * Dattilo W. et al. 2019. MEXICO ANTS: incidence and abundance along the Nearctic-Neotropical interface. Ecology https://doi.org/10.1002/ecy.2944
 * Donoso D. A. 2014. Assembly mechanisms shaping tropical litter ant communities. Ecography 37 doi: 10.1111/j.1600-0587.2013.00253.x
 * Fernández, F. and S. Sendoya. 2004. Lista de las hormigas neotropicales. Biota Colombiana Volume 5, Number 1.
 * Kaspari M., D. Donoso, J. A. Lucas, T. Zumbusch, and A. D. Kay. 2012. Using nutritional ecology to predict community structure: a field test in Neotropical ants. Ecosphere 3(11): art.93.
 * Kempf, W.W. 1972. Catalago abreviado das formigas da regiao Neotropical (Hym. Formicidae) Studia Entomologica 15(1-4).
 * Longino J. T., and R. K. Colwell. 2011. Density compensation, species composition, and richness of ants on a neotropical elevational gradient. Ecosphere 2(3): 16pp.
 * 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.
 * Reynoso-Campos J. J., J. A. Rodriguez-Garza, and M. Vasquez-Bolanos. 2015. Hormigas (Hymenoptera: Formicidae) de la Isla Cozumel, Quintana Roo, Mexico (pp. 27-39). En: Castaño Meneses G., M. Vásquez-Bolaños, J. L. Navarrete-Heredia, G. A. Quiroz-Rocha e I. Alcalá-Martínez (Coords.). Avances de Formicidae de  México.  UNAM,  Universiad  de  Guadalajara, Guadalajara, Jalisco.
 * Silva R.R., and C. R. F. Brandao. 2014. Ecosystem-Wide Morphological Structure of Leaf-Litter Ant Communities along a Tropical Latitudinal Gradient. PLoSONE 9(3): e93049. doi:10.1371/journal.pone.0093049
 * Ulyssea M.A., C. E. Cereto, F. B. Rosumek, R. R. Silva, and B. C. Lopes. 2011. Updated list of ant species (Hymenoptera, Formicidae) recorded in Santa Catarina State, southern Brazil, with a discussion of research advances and priorities. Revista Brasileira de Entomologia 55(4): 603-611.