Adelomyrmex minimus

This species is still known only from the holotype. It is apparently a Pacific slope version of the Atlantic slope Adelomyrmex foveolatus, differing only in the smaller eyes and perhaps smaller size. But these are both traits that vary, and sample sizes are insufficient to assess morphological distinctness. (Longino 2012)

Identification
Very similar to Adelomyrmex foveolatus, but distinguished by: smaller size, eyes reduced to one ommatidium; foveae more dense, hypostomal teeth larger, mesosomal sides with some rugulae and color lighter.

Key to Adelomyrmex of the New World mainland

Distribution based on Regional Taxon Lists
Neotropical Region: Costa Rica.

Castes
Known only from the worker caste.

Nomenclature

 *  minimus. Adelomyrmex minimus Fernández, in Fernández & Mackay, 2003: 602 (w.) COSTA RICA. See also: Fernández, 2003b: 24.

Worker
Mandibles with 5 teeth, decreasing in size from the apical. The angle between basal tooth of masticatory border and tooth of basal border well developed. Anterior margin of clypeal plate slightly concave. Eyes with 1 ommatidium. Hypostomal tooth medium sized, stout. Mesosoma evenly convex, interrupted only by the deep metanotal groove. Propodeal spines about as long as wide. Petiole rounded above. Postpetiole with median carinae on posterior side. Head smooth and shining with dense and large foveae in posterior part, sides rugo-foveolated, medial area with about 7 longitudinal rugulae. Promesonotum smooth and shining. Sides of mesosoma smooth and shining with some irregular striae. Posterior face of propodeum with several transverse carinae. Most of petiole and postpetiole smooth and shining. Dorsal pilosity moderately long, dense. Body light brown.

Type Material
Fernández (2003b) - holotype worker (Puntarenas, Costa Rica) from the stomach of Dendrobates granuliferus frog.