Rhopalothrix stannardi

Recent collections of this species are from lowland wet to moist forest habitat, from 70–270m elevation. The type is apparently from a somewhat higher site near Ocosingo. All recent specimens are from Winkler samples of sifted leaf litter. In quantitative sampling carried out during Project LLAMA, this species occurred in 4 of 100 miniWinkler samples at a lowland Chiapas site and in 7 of 100 samples from in and near Tikal National Park in Guatemala. (Longino & Boudinot, 2013)

Distribution based on Regional Taxon Lists
Neotropical Region: Belize, Guatemala, Mexico.

Castes
Known only from the worker caste.

Nomenclature

 *  stannardi. Rhopalothrix stannardi Brown & Kempf, 1960: 236, fig. 57 (w.) MEXICO.

Worker
Holotype. TL 2.7, HL 0.54, HW 0.56 (CI 104), ML 0.15, WL 0.55 mm.

Very similar to R. isthmica, but differing in the narrower head and otherwise as follows:

1. Blunt transverse crests across head, and corresponding sulci, well defined; more as in R. weberi. Sides of occipital lobes nearly evenly rounded. Eyes minute, each with a single facet.

2. Mandibles more slender, at their bases only about half as wide (0.09-0.10 mm) as the labral shield; in isthmica, the mandibular bases are distinctly more than half as wide as the labral shield. Subapical tooth about 0.12 mm long, slender and acute, feebly recurved. Dentition (basad of reclinate tooth at base of subapical tooth) consisting only of a subbasal denticle, a small middle tooth, and beyond the latter another very small denticle. The down turned apical tooth is only about 1/3 the length of the subapical tooth, from which it is separated by two smaller but acute intercalary teeth.

3. Labral shield broader than long, sides subparallel and nearly straight, anterolateral corners subacute; anterior margin broadly and very shallowly concave, and within this feebly tri-emarginate or sinuate, in no sense deeply excavated or notched. Each anterolateral corner bears a stout, tapered, anteriorly directed "trigger-hair".

4. Propodeal teeth with more evenly rounded infradental lamellae. Petiolar node more rounded behind, and with only a feeble ventral swelling. Alitrunk in profile appearing more evenly, and very gently, convex; metanotal impression very feeble.

5. Erect pilosity as in R. isthmica, but slightly less abundant and conspicuous, largely confined to angles of scapes and apical half of gaster. Extensor surfaces of tibiae at apices, and of the tarsi their lengths, with conspicuous short, inclined, paddle-shaped hairs. Underside of gaster just before apex with 10-12 peculiar, short, thorn-like projections, irregular in size, position and inclination, appearing to be outgrowths of the integument, but which may be either artifacts or modifications of the blunt setae found in the same positions on R. isthmica. Pubescence suppressed, apparent only toward gastric apex, where quite sparse.

6. Sculpture as in R. isthmica, normally exposed surfaces opaque, punctulate-granulose with minute tuberculae. Color sordid testaceous, head and anterior alitrunk slightly more brownish.

Longino and Boudinot (2013) - HW 0.53–0.59 (n=5); mandible with three widely spaced denticles on masticatory margin, middle denticle largest; subapical tooth with minute reclinate denticle at base; subapical tooth about twice as long as apical tooth; intercalary teeth prominent, one closest to apical tooth about half as long as apical tooth; labrum subrectangular, outer margins diverging anteriorly, anterior margin very shallowly and evenly concave, with minute notch medially; posterior margin of clypeus elevated above anterior face; arcuate grooves and ridges of face very shallow; mesosomal dorsum evenly and shallowly convex in profile, metanotal groove not or very weakly impressed; propodeal tooth obtuse to right angled, infradental lamella broad and descending almost perpendicularly from tooth; about 12 squamiform setae on posterior half of first gastral tergite.

Type Material
Holotype a unique, taken by Berlese or other sifting apparatus at Finca el Real, Ocosingo Valley, Chiapas, Mexico, July 1-7, 1950 (c. and M. Goodnight and L. J. Stannard leg.); deposited in.

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
 * Fernandes, P.R. XXXX. Los hormigas del suelo en Mexico: Diversidad, distribucion e importancia (Hymenoptera: Formicidae).
 * Kempf, W.W. 1972. Catalago abreviado das formigas da regiao Neotropical (Hym. Formicidae) Studia Entomologica 15(1-4).
 * Lachaud J. P., and G. Perez-Lachaud. 2013. Revisión preliminar de las hormigas de Campeche y Quintana Roo, México, con base en la colección de Arthropoda del Colegio de la Frontera Sur. In Formicidae de Mexico (eds. M. Vasquez-Bolanos, G. Castano-Meneses, A. Cisneros-Caballero, G. A. Quiroz-Rocha, and J. L. Navarrete-Heredia) p21-32.
 * 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.
 * Mirmecofauna de la reserva ecologica de San Felipe Bacalar
 * Vásquez-Bolaños M. 2011. Lista de especies de hormigas (Hymenoptera: Formicidae) para México. Dugesiana 18: 95-133