Epopostruma

While Epopostruma can be fairly common they are often overlooked. Workers are slow-moving and most lie motionless when disturbed. Their nests are small, with up to about 100 workers, and are found in open soil or in soil under rocks, logs or small sticks. They also nest in cracks in large rocks. When nesting in open soil they are often found near the bases of trees.

Almost all species forage at night although one species is known to occasionally forage on mallee stems during the day. They are also regularly found in leaf litter. Workers have been attracted to honey baits on trees in the late evening and at night. Their elongate and specialised mandibles form a type of snap-trap which is used to captured soft-bodied prey such as Collembola.

Identification
The antennae are 6 segmented (including the scape) and the scapes pass below the eyes when laid back against the head in their normal resting position. The mandibles are thin and elongate and when fully closed they are separated by a broad gap for most of their length, touching only at the tips. These characters will separate Epopostruma from all other Australian ants, including the superficially similar Colobostruma, Eurhopalothrix, Mesostruma and Rhopalothrix.

Regional Key
World species

Nomenclature

 *  EPOPOSTRUMA [Myrmicinae: Dacetini]
 * Epopostruma Forel, 1895f: 422 [as subgenus of Strumigenys]. Type-species: Strumigenys (Epopostruma) quadrispinosa, by subsequent designation of Wheeler, W.M. 1911f: 163.
 * Epopostruma raised to genus: Emery, 1897c: 573.
 * Epopostruma senior synonym of Hexadaceton: Taylor & Brown, D.R. 1985: 63; Bolton, 1999: 1681; Shattuck, 2000: 53.
 * Epopostruma senior synonym of Colobostruma, Mesostruma: Baroni Urbani & De Andrade, 2007: 94.
 * HEXADACETON [junior synonym of Epopostruma]
 * Hexadaceton Brown, 1948e: 120. Type-species: Hexadaceton frosti, by original designation.
 * Hexadaceton junior synonym of Epopostruma: Taylor & Brown, D.R. 1985: 63; Bolton, 1999: 1681; Shattuck, 2000: 53.

Additional References

 * Bolton, B. (1999). Ant genera of the tribe Dacetonini (Hymenoptera: Formicidae). Journal of Natural History 33: 1639–1689 [generic status]
 * Brown, W. L., Jr., Wilson, E. O. (1959). The evolution of the dacetine ants. Quarterly Review of Biology 34: 278–294 [overview]
 * Brown, W. L., Jr. (1954). A preliminary report on dacetine ant studies in Australia. Annals of the Entomological Society of America. 46 : 465–471 [tribal placement]
 * Brown, W. L., Jr. (1988). Data on Malpighian tubule numbers in ants (Hymenoptera: Formicidae). pp. 17–27 in Trager, J. C. Advances in Myrmecology. Leiden : E. J. Brill. xxvii + 551 pp.
 * Crozier, R. H. (1968). The chromosomes of three Australian dacetine ant species (Hymenoptera: Formicidae). Psyche (Cambridge). 75: 87–90
 * Taylor, R. W. (1991). Nomenclature and distribution of some Australasian ants of the Myrmicinae (Hymenoptera: Formicidae). Memoirs of the Queensland Museum 30: 599–614