Neivamyrmex alfaroi

This species is only known from queens and/or workers and has yet to be associated with males.

Identification
Jack Longino:

Posterior face of propodeum strongly concave, distinctly indented below a rounded juncture of dorsal and posterior faces; eye with distinct convex cornea; head smooth and with sparse small puncta, distinctly shiny; surface of body red brown, lacking violaceous reflections.

Similar species: Neivamyrmex iridescens.

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

Biology
Jack Longino: This species occurs in lowland wet to moist forest, including seasonally dry scrubby vegetation at 300m elevation on the road to Monteverde. At Cedral in Corcovado National Park I watched a spectacular nocturnal raid on a Cyphomyrmex salvini nest. At 2000hrs I watched a very dense, fan-shaped swarm slowly advanced up a thin treetrunk. Individual ants moved very rapidly, and they were so dense that you could see swirls and eddies within the swarm. They attacked a Cyphomyrmex colony that was nesting in an aroid clump several meters high. The Cyphomyrmex ran out carrying brood, and soon were covering surrounding vegetation. At Llorona, also in Corcovado, and at Estrella, at 300m elevation on the road to Monteverde, I saw columns during the day. In a scrubby forest patch near Quepos, while collecting at night, I found a column on the ground. I put a stick with a Camponotus linnaei nest on the column, and the Neivamyrmex immediately attacked, dragging out alate queens and males.

Nomenclature

 *  alfaroi. Eciton alfaroi Emery, 1890b: 39 (w.) COSTA RICA. [Also described as new by Emery, 1894k: 45.] Borgmeier, 1949: 202 (q.). Combination in E. (Acamatus): Emery, 1894c: 182 (in text); in E. (Neivamyrmex): Borgmeier, 1949: 201; in Neivamyrmex: Borgmeier, 1953: 6. See also: Borgmeier, 1955: 533.

References based on Global Ant Biodiversity Informatics

 * Smith M. A., W. Hallwachs, D. H. Janzen. 2014. Diversity and phylogenetic community structure of ants along a Costa Rican elevational gradient. Ecography 37(8): 720-731.
 * Watkins J. F., II 1976. The identification and distribution of New World army ants (Dorylinae: Formicidae). Waco, Texas: Baylor University Press, 102 pp