Epopostruma natalae

Epopostruma natalae, one of the most commonly collected species in the genus, is known from just south of Sydney, New South Wales, south and west through the Australian Capital Territory, Victoria and northern Tasmania to the vicinity of Adelaide, South Australia. It has been found in dry sclerophyll, dry sclerophyll on a hillside and near a hill top, medium sclerophyll, a wet sclerophyll flat and in low heath vegetation. Nests or foragers have been encountered under rocks, in a mossy clump at the base of a tree in dry white powder soil, in a damp patch of soil (Permian) at the base of a Box tree, in soil, in soil at base of tree and in leaf litter.

Identification
Epopostruma natalae can be separated from others in the quadrispinosa species group by the following combination of characters.


 * Petiolar teeth diverging slightly laterally so that their tips extend outwards beyond the lateral margins of the petiole.
 * A row of short longitudinal rugae are present on the anterior margin of the gaster immediately behind the postpetiole.
 * The posterolateral corners of the postpetiole form a weak angle and are not drawn outwards into a tooth or spine.
 * The gaster is uniform brown in colour.
 * The body colour is generally brown or sometimes light brown.

Key to Epopostruma Species

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 *  natalae. Epopostruma natalae Shattuck, in Bolton, 2000: 65, figs. 66, 77, 93 (w.q.m.) AUSTRALIA.

Description
In full face view the lateral margin of the head between the eye and the posterior corner angular. Pronotal spines present, elongate. Posterior section of metanotum in approximately the same plane as the dorsal face of propodeum, the junction of these plates a very shallow depression. Posterior face of propodeum between bases of spines and propodeal lobes with thin flanges. Petiolar spines generally present and thin, sometimes reduced to a protuberance. Anterior face of postpetiole shorter than the dorsal face and separated from it by a broadly rounded angle; sides of postpetiole approximately vertical and rounding gradually from dorsal to posterior surfaces, in dorsal view the lateral margins parallel. Dorsum of petiole, postpetiole and gaster with short, gently curved erect hairs. First gastral tergite smooth or nearly so, at most with only very weak, widely spaced striations; a row of short rugae present on the anterior margin immediately behind the postpetiole. Body colour generally brown, sometimes lighter; appendages generally same colour as body, occasionally lighter; gaster uniformly coloured.

Measurements

Holotype worker. TL 4.2mm, HL 0.93mm, HW 0.88mm, CI 95, MandL 0.45mm, MandI 48, SL 0.53mm, SI 60, PronW 0.61mm, ML 1.09mm.

CI (cephalic index) - HW/HL X 100. HL (head length) - The length of the head capsule excluding the mandibles, measured in full face view in a straight line from the mid point of the anterior clypeal margin to the mid point of the occipital margin. In species where one or both of these margins is concave the measurement is taken from the mid point of a transverse line that spans the apices of the projecting portions. HW (head width) - The maximum width of the head in full face view, excluding the eyes. MandI (mandibular index) - ML/HL X 100. MandL (mandible length) - The straight line length of the mandible at full closure, measured in the same plane for which the HL measurement is taken (i.e. full face view), from the mandibular apex to the anterior clypeal margin, or to the transverse line connecting the anteriormost points in those taxa where the margin is concave medially. ML (mesosomal length) (= Weber's length) - The diagonal length of the mesosoma in profile from the point at which the pronotum meets the cervical shield to the posterior basal angle of the metapleuron. PronW (pronotal width) - The maximum width of the pronotum in dorsal view. (Projecting spines, tubercles or other cuticular prominences at the pronotal humeral angles are ignored.) SI (scape index) - SL/HW X 100. SL (scape length) - The maximum straight line length of the scape, excluding the basal constriction or neck that occurs just distal of the condylar bulb. TL (total length) - The total outstretched length of the ant from the mandibular apex to the gastral apex; when measured in profile the sum of ML + HL + ML + lengths of waist segments + length of gaster.