Stigmacros

Stigmacros is only known to occur in Australia. Species are general predators and forage on the ground, in leaf litter and arboreally on trees and shrubs. Most nest in the soil, usually under or between rocks, although a few are known to nest under bark or in dead wood on living trees. They can be relatively common with 4 or 5 species being found together at some sites.

Identification
The antennae are 11 segmented (including the scape). The propodeum armed with one or more pairs of spines, teeth or protuberances. The top of the petiole is usually rounded or angula, but in some it is armed with a pair of spines.

Most species of Stigmacros can be recognised by their small overall size and distinct spines on the propodeum and top of the petiole. However, some have the propodeal spines reduced and the top of the petiole rounded. These ants look very similar to the dolichoderine genus Ochetellus or smaller species of Prolasius in overall body shape, especially in having the rear face of the propodeum straight or concave. However, Stigmacros can be distinguished from these as they have 11 segmented antennae.

Castes


Worker of Stigmacros from Queensland.

Nomenclature

 *  STIGMACROS [Formicinae: Lasiini]
 * Stigmacros Forel, 1905b: 179 [as subgenus of Acantholepis]. Replacement name for Acrostigma Forel, 1902h: 477. [Junior homonym of †Acrostigma Emery, 1891a: 149.]
 * Stigmacros raised to genus: Wheeler, W.M. 1922a: 696.
 * Stigmacros senior synonym of Campostigmacros, Chariostigmacros, Cyrtostigmacros, Hagiostigmacros, Pseudostigmacros: Taylor & Brown, D.R. 1985: 145.
 * ACROSTIGMA [junior homonym, see Stigmacros]
 * Acrostigma Forel, 1902h: 477 [as subgenus of Acantholepis]. Type-species: Acantholepis (Acrostigma) froggatti, by subsequent designation of Wheeler, W.M. 1911f: 158. [Junior homonym of †Acrostigma Emery, 1891a: 149, above.]
 * Stigmacros Forel, 1905b: 179, replacement name for Acrostigma Forel.
 * CAMPOSTIGMACROS [junior synonym of Stigmacros]
 * Campostigmacros McAreavey, 1957: 25 [as subgenus of Stigmacros]. Type-species: Acantholepis aemula, by original designation.
 * Campostigmacros junior synonym of Stigmacros: Taylor & Brown, D.R. 1985: 145.
 * CHARIOSTIGMACROS [junior synonym of Stigmacros]
 * Chariostigmacros McAreavey, 1957: 23 [as subgenus of Stigmacros]. Type-species: Stigmacros (Chariostigmacros) hirsuta, by original designation.
 * Chariostigmacros junior synonym of Stigmacros: Taylor & Brown, D.R. 1985: 145.
 * CYRTOSTIGMACROS [junior synonym of Stigmacros]
 * Cyrtostigmacros McAreavey, 1957: 35 [as subgenus of Stigmacros]. Type-species: Acantholepis (Acrostigma) australis, by original designation.
 * Cyrtostigmacros junior synonym of Stigmacros: Taylor & Brown, D.R. 1985: 145.
 * HAGIOSTIGMACROS [junior synonym of Stigmacros]
 * Hagiostigmacros McAreavey, 1957: 19 [as subgenus of Stigmacros]. Type-species: Stigmacros barretti, by original designation.
 * Hagiostigmacros junior synonym of Stigmacros: Taylor & Brown, D.R. 1985: 145.
 * PSEUDOSTIGMACROS [junior synonym of Stigmacros]
 * Pseudostigmacros McAreavey, 1957: 24 [as subgenus of Stigmacros]. Type-species: Stigmacros (Pseudostigmacros) inermis, by original designation.
 * Pseudostigmacros junior synonym of Stigmacros: Taylor & Brown, D.R. 1985: 145.