Probolomyrmex

Pantropically distributed but rare wherever they do occur (Taylor, 1965a; Agosti, 1994; O'Keefe & Agosti, 1997; Ito, 1998; Fisher, 2007). A scarcity of material was a challenge for the first global taxonomic revision. It included just 57 specimens belonging to nine species (Taylor, 1965a). Since Taylor's (1965a) revision further new species have been described (e.g. Agosti, 1994; O'Keefe & Agosti, 1997; Eguchi et al., 2006; Fisher, 2007; Bolton, 2012). 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)). An Asian species seems to be a specialised predator of millipedes (Ito, 1998), though it remains unclear if the other genus members prefer the same diet.

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

Species richness
Species richness by country based on regional taxon lists (countries with darker colours are more species-rich). View Data



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.