Formica postoculata

Identification
The scape of this species is without erect hairs (except at the apex). The tibiae are without erect hairs, except for a row of bristles on the flexor surface. The dorsum of the head has a number of erect hairs, and the ventral surface has a few scattered hairs. The pronotum has several erect hairs, and the metanotum has a few hairs. The propodeum normally is without erect hairs, although 1 may be present. The petiole lacks erect hairs; the firs tergum has several, scattered, erect hairs.

The queen and male are unknown.

The convex occipital margin and lack of hairs on the tibiae (other than the row of bristles) separate this species from most others, except for Formica indianensis, Formica difficilis and Formica querquetulana. It can be separated from two of these species (F. difficilis and F. querquetulana) by the lack of erect hairs on the propodeum and petiole. Separating this species from F. indianensis is more problematic. Often the dorsum of the head of F. indianensis is without erect hairs, and when they are present, they are usually few in number (fewer than 10). Formica postoculata usually has a number of hairs on the dorsal surface of the head (more than 10).

Distribution based on Regional Taxon Lists
Nearctic Region: United States.

Biology
This species is likely to be a temporary parasite of another species of Formica, but its host is.

Nomenclature

 *  postoculata. Formica postoculata Kennedy & Dennis, 1937: 540, figs. 16-18 (w.) U.S.A.

Taxonomic Notes
It is possible that Formica indianensis will be found to be a synonym of Formica postoculata, when more material of both species becomes available.

References based on Global Ant Biodiversity Informatics

 * Carroll T. M. 2011. The ants of Indiana (Hymenoptera: Formicidae). Master's Thesis Purdue university, 385 pages.
 * Coovert G. A. 2005. The Ants of Ohio (Hymenoptera: Formicidae). Ohio Biological Survey, Inc. 15(2): 1-207.
 * Coovert, G.A. 2005. The Ants of Ohio (Hymenoptera: Formicidae) Ohio Biological Survey Bulletin New Series Volume 15(2):1-196
 * Francoeur A. 2010. Liste des especes de fourmis (Formicides, Hymenopteres). Entomofaune du Quebec. Document Faunique no. 1, Version 5, 0. 1-10 pp.
 * Ivanov K. 2019. The ants of Ohio (Hymenoptera, Formicidae): an updated checklist. Journal of Hymenoptera Research 70: 65–87.
 * Ivanov K., L. Hightower, S. T. Dash, and J. B. Keiper. 2019. 150 years in the making: first comprehensive list of the ants (Hymenoptera: Formicidae) of Virginia, USA. Zootaxa 4554 (2): 532–560.
 * Kennedy C. H., and C. A. Dennis. 1937. New ants from Ohio and Indiana, Formica prociliata, F. querquetulana, F. postoculata and F. lecontei, (Formicidae: Hymenoptera). Ann. Entomol. Soc. Am. 30: 531-544.