Strumigenys epinotalis

The species was described from "1 female and 4 workers ... collected by Dr. George C. Wheeler from Talia Farm, Estrella Valley, Costa Rica, June 18, 1924 (Weber 1934)." Dozens of sifted litter samples from Atlantic slope wet forest, including sites near the type locality, have not produced examples of this species. The species skwarrae, synonymized with epinotalis by Brown (1953), was "described from 15 specimens representing four colonies, all taken by Dr. Skwarra in Tillandsia streptophylla in two localities: Tlacocintla (type locality; 487 and 494) and Mirador (153 and 290) [Wheeler 1934]." Bolton (2000) reports Mexican collections by Dressler and by Dejean, both researchers who work with epiphytes. These observations all suggest the species is arboreal. (Longino, Ants of Costa Rica)

Identification
Bolton (2000) - A member of the Strumigenys schulzi-group. A very distinctive small species that is immediately characterised by its dentition and pilosity. Unlike most species in this group the postpetiole disc is completely smooth and the petiole ventrally has a distinctly spongiform longitudinal crest. The curved row of spoon-shaped hairs that adorn the top of the mid -pronotal arched-transverse ridge is very distinctive in dorsal view and is a unique development of this species.

Longino (Ants of Costa Rica) - Mandibles in side view straight, not broadly curved ventrally; mandibles relatively short, subtriangular, much of the apical portion meeting along a serially toothed masticatory margin when closed (former Smithistruma); leading edge of scape with a row of conspicuous projecting curved hairs, of which those distal to the subbasal bend distinctly curve toward the base of the scape; pronotal humeral hair absent; dorsal surfaces of middle and hind tibiae with decumbent to appressed short spatulate hairs; face punctate; side of mesosoma completely punctate; petiole with ventral spongiform appendage; postpetiole disc completely smooth; mid-pronotal arched-transverse ridge with row of spoon-shaped hairs, most visible in dorsal view; first gastral tergite smooth behind the basigastral costulae, the latter distinct and extending at least the basal fifth to quarter of the length of the tergite, not masked by dense sculpture; infradental lamella of propodeum strongly developed.

Distribution based on Regional Taxon Lists
Nearctic Region: United States. Neotropical Region: Brazil, Costa Rica, Ecuador, Mexico, Panama, Paraguay.

Biology
Brown (1964) - Two new records from southern Mexico further confirm the tendency of this species to nest, like other schulzi-group members, in plant cavities: Veracruz, Veracruz, in hollow twigs (N. L. H. Krauss leg.); Laguna Ocotal Grande, 950 m. Ocosingo Valley, Chiapas, in epiphytic Tillandsia bulb in pine forest (R. L. Dressler leg.).

Nomenclature

 *  epinotalis. Strumigenys (Cephaloxys) studiosi subsp. epinotalis Weber, 1934a: 46 (w.q.) COSTA RICA. Combination in Smithistruma: Brown, 1953g: 101; in Pyramica: Bolton, 1999: 1673; in Strumigenys: Baroni Urbani & De Andrade, 2007: 119. Raised to species and senior synonym of skwarrae: Brown, 1953g: 101. See also: Bolton, 2000: 219.
 * skwarrae. Strumigenys (Cephaloxys) skwarrae Wheeler, W.M. 1934g: 177 (w.) MEXICO. Junior synonym of epinotalis: Brown, 1953g: 101.

Worker
Bolton (2000) - TL 1.9-2.1, HL 0.49-0.56, HW 0.39-0.42, CI 73-79, ML 0.11-0.12, MI 20-22, SL 0.25-0.27, SI 62-66, PW 0.25-0.28, AL 0.50-0.56 (to measured). Tooth 3 from the base elongate and spiniform, longer than 1-2 or 4-5, all of which are about of equal length and acute. Anterior clypeal margin evenly shallowly convex. Eye with 5-6 (rarely 7) ommatidia in the longest row. Scape broad in dorsal view, ca 4.5 X longer than its maximum width. Ground-pilosity of head of conspicuous medially curved spoon-shaped hairs. Vertex behind highest point with a transverse row of 4 longer, more erect and somewhat stouter hairs. Apicoscrobal hair thick, anteriorly curved and spoon-shaped, longer and more strongly laterally prominent than any other hair on the margin. Pronotal humeral hair absent. Pronotal dorsum at its midlength with a broadly arched low transverse ridge that bears a row of anteromedially curved spoon-shaped hairs. Mesonotum with curved spoon-shaped ground-pilosity but without standing hairs of any form. Head and alitrunk usually densely reticulate-punctate on every surface, but rarely the katepisternum with a small shining patch. Lamella on propodeal declivity broad. Petiole node markedly broader than long in dorsal view; in profile with a narrow but distinct longitudinal spongiform crest ventrally. Disc of postpetiole smooth and shining, the lateral and ventral postpetiolar spongiform lobes large. Basigastral costulae extending over the basal quarter to third of the sclerite, sharply defined; tergite otherwise smooth and shining. Hairs on first gastral tergite numerous, suberect to erect, stout straight and thickened or remiform apically. First gastral stemite in profile with narrow but distinct basal spongiform pad.

Type Material
Bolton (2000) - Syntype workers and queen, COSTA RICA: Estrella Valley, Talia Farm, 18.vi.1924 (G. C. Wheeler) [examined].

References based on Global Ant Biodiversity Informatics

 * Bolton, B. 2000. The Ant Tribe Dacetini. Memoirs of the American Entomological Institute 65
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 * Branstetter M. G. and L. Sáenz. 2012. Las hormigas (Hymenoptera: Formicidae) de Guatemala. Pp. 221-268 in: Cano E. B. and J. C. Schuster. (eds.) 2012. Biodiversidad de Guatemala. Volumen 2. Guatemala: Universidad del Valle de Guatemala, iv + 328 pp
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 * Kempf, W.W. 1972. Catalago abreviado das formigas da regiao Neotropical (Hym. Formicidae) Studia Entomologica 15(1-4).
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 * Maes, J.-M. and W.P. MacKay. 1993. Catalogo de las hormigas (Hymenoptera: Formicidae) de Nicaragua. Revista Nicaraguense de Entomologia 23.
 * Ryder Wilkie K.T., A. L. Mertl, and J. F. A. Traniello. 2010. Species Diversity and Distribution Patterns of the Ants of Amazonian Ecuador. PLoS ONE 5(10): e13146.doi:10.1371/journal.pone.0013146
 * Silva T. S. R., and R. M. Feitosa. 2019. Using controlled vocabularies in anatomical terminology: A case study with Strumigenys (Hymenoptera: Formicidae). Arthropod Structure and Development 52: 1-26.
 * Vasquez-Bolanos M. 2011. Checklist of the ants (Hymenoptera: Formicidae) from Mexico. Dugesiana 18(1): 95-133.
 * Vásquez-Bolaños M. 2011. Lista de especies de hormigas (Hymenoptera: Formicidae) para México. Dugesiana 18: 95-133
 * Weber N. A. 1934. Notes on neotropical ants, including the descriptions of new forms. Revista de Entomologia (Rio de Janeiro) 4: 22-59.