Probolomyrmex

These rarely encountered ants are cryptic foragers in leaf litter and presumably also forage below the ground surface. Nests are small, complete colonies containing from a few up to about 20 workers, and are found in soil under rocks, in leaf litter or in rotten wood. Most species in this genus have normal, fully winged queens, one species (Probolomyrmex guanacastensis) is known to have ergatoid queens (O'Keefe and Agosti (1997)).

Identification
The frontal lobes are reduced to a narrow, sharp ridge between the antennal sockets and the insertion point of the antennae are clearly visible when viewed from the front. The eyes are absent. The lack of eyes, combined with the exposed antennal insertion points, will allow identification of these ants.

Identification Keys
Australia and Melanesia

Nomenclature

 *  PROBOLOMYRMEX [Proceratiinae: Probolomyrmecini)
 * Probolomyrmex Mayr, 1901b: 2. Type-species: Probolomyrmex filiformis, by monotypy.
 * Probolomyrmex senior synonym of Escherichia: Taylor, 1965d: 346.
 * ESCHERICHIA [junior synonym of Probolomyrmex]
 * Escherichia Forel, 1910c: 245. Type-species: Escherichia brevirostris, by monotypy.
 * Escherichia junior synonym of Probolomyrmex: Taylor, 1965d: 346.

Additional References

 * [[Media:Agosti 1995.pdf|Agosti, D. 1995 [1994]. A revision of the South American species of the ant genus Probolomyrmex (Hymenoptera: Formicidae). J. N. Y. Entomol. Soc. 102: 429-434 PDF]]
 * Shattuck, S.O., Gunawardene, N.G. & Heterick, B. 2012. A revision of the ant genus Probolomyrmex (Hymenoptera: Formicidae: Proceratiinae) in Australia and Melanesia. Zootaxa 3444: 40–50.