Strumigenys cassicuspis

Occurs in wet forest habitats, in leaf litter on the forest floor (Longino, Ants of Costa Rica).

Identification
Bolton (2000) - A member of the Strumigenys schulzi-group. Closely related to Strumigenys microthrix and Strumigenys stauroma, especially the latter species. Differences separating microthrix from both cassicuspis and stauroma are listed under microthrix; the other two are distinguished as follows.

S. cassicuspis: Posterior margin of clypeus without a transverse row of 4 erect hairs that are much longer and more conspicuous than the dense stubbly erect ground-pilosity that arises elsewhere on clypeus and on dorsal head behind clypeus. Occipital lobes in profile or in full-face view without numerous small peaks or tubercles from which short stubbly hairs arise. Dorsal surfaces of pronotum and mesonotum without suberect to erect short stubbly hairs.

S. stauroma: Posterior margin of clypeus with a transverse row of 4 erect hairs that are much longer and more conspicuous than the dense stubbly erect ground-pilosity that arises elsewhere on the clypeus and on dorsal head behind clypeus. Occipital lobes in profile or in full-face view with numerous small peaks or tubercles from which short stubbly hairs arise. Dorsal surfaces of pronotum and mesonotum with numerous suberect to erect short stubbly hairs present.

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); head relatively broad, CI 77-83; leading edge of the scape with entirely anteriorly directed short spatulate hairs; color red-brown; face punctate; disc of postpetiole reticulate-punctate; surface of face granular but not tuberculate; cephalic dorsum at level of frontal lobes without a transverse row of hairs that are much longer than the surrounding pilosity; face but not promesonotal dorsum covered with short, stiff, erect setae (stubble).

It is very similar to two other species: microthrix and stauroma. The former has no stubble. The latter has stubble, but also is covered with sharp low tubercles, giving the surface a very rough look.

Distribution based on Regional Taxon Lists
Neotropical Region: Belize, Colombia, Costa Rica, Guatemala, Honduras, Nicaragua.

Nomenclature

 *  cassicuspis. Pyramica cassicuspis Bolton, 2000: 216, fig. 147 (w.) COSTA RICA. Combination in Strumigenys: Baroni Urbani & De Andrade, 2007: 117

Worker
Holotype. TL 2.3, HL 0.64, HW 0.50, CI 78, ML 0.10, MI 16, SL 0.28, SI 56, PW 0.33, AL 0.62. Anterior clypeal margin transverse. Dentition as described in introduction to group. Occipital lobes strongly expanded laterally in full-face view. Scape markedly dorsoventrally flattened and broad in dorsal view. Freely projecting hairs on leading edge of scape spoon-shaped, at right-angles to long axis of scape or curved toward its apex; no hairs conspicuously curved toward the base of the scape. Apicoscrobal and pronotal humeral hairs absent. With head in full-face view lateral margins of occipital lobes with abundant short stubbly projecting erect hairs. Occipital lobes without minute peaks or tubercles. Dorsum of head without a transverse row of elongate standing hairs just behind highest point of vertex but clypeus and dorsum of head with short stubbly dense erect pilosity. Clypeus close to its posterior border without a transverse palisade-like row of much longer stouter hairs. Promesonotum in dorsal view flattened and very broad, without standing pilosity of any form. Femoral gland bullae elongate and conspicuous, especially on foreleg; bullae very obviously much longer than broad. Petiole in profile without trace of ventral spongiform tissue. Lateral spongiform lobes and posterior collar of petiole apparently absent, actually narrow and secondarily sclerotised, and pigmented so as to be virtually indistinguishable from the surrounding cuticle. With petiole in profile the dorsal length of the node distinctly greater than the height of its anterior face; in dorsal view the node conspicuously longer than broad. Spongiform strip at base of first gastral sternite vestigial to absent. Entirety of head and alitrunk reticulate-punctate. First gastral tergite with very short basigastral costulae, behind which the sclerite is glassy smooth.

Paratypes. TL 2.1-2.3, HL 0.60-0.66, HW 0.46-0.50, CI 76-78, ML 0.08-0.10, MI 13-16, SL 0.24-0.28, SI 52-56, PW 0.31-0.34, AL 0.60-0.64 (4 measured).

Type Material
Holotype worker, Costa Rica: Provo Alajuela, Rio Penas Blancas, 10°19'N, 84°43'W, 800 m., 26-28.iv.1987, wet forest, ex sifted leaf litter, #1579-s (J. Longino). Paratypes. 2 workers with same data as holotype; 2 workers Costa Rica: Provo Heredia, Est. Biol. La Selva, 10°26'N, 84°00'W, 50 m., 14.x.1991, wet forest, ex sifted leaf litter, #3078-s (J. Longino).

References based on Global Ant Biodiversity Informatics

 * Bolton, B. 2000. The Ant Tribe Dacetini. Memoirs of the American Entomological Institute 65
 * 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
 * Fernández, F. and S. Sendoya. 2004. Lista de las hormigas neotropicales. Biota Colombiana Volume 5, Number 1.
 * Longino J. T. 2013. Ants of Honduras. Consulted on 18 Jan 2013. https://sites.google.com/site/longinollama/reports/ants-of-honduras
 * Longino J. T. L., and M. G. Branstetter. 2018. The truncated bell: an enigmatic but pervasive elevational diversity pattern in Middle American ants. Ecography 41: 1-12.
 * 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.