Iridomyrmex anderseni

Identification
This medium-sized member of the I. viridigaster complex is known only from the holotype from inland South Australia. The characters separating this form from I. viridigaster are weak, and more material is needed to confirm that it is a bona fide species. The taxon is discussed in Shattuck (1993b).

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 *  anderseni. Iridomyrmex anderseni Shattuck, 1993b: 1310, figs. 22, 23, 38 (w.) AUSTRALIA. See also: Heterick & Shattuck, 2011: 43.

Description
Worker Description. Head. Posterior margin of head weakly concave; erect setae on posterior margin in full- face view set in a row; sides of head noticeably convex; erect genal setae present on sides of head in full-face view. Ocelli absent; in full-face view, eyes set above midpoint of head capsule; in profile, eye set anteriad of head capsule; eye asymmetrical, curvature of inner eye margin more pronounced than that of its outer margin. Frontal carinae concave; antennal scape failing to attain posterior margin of head. Erect setae on scape absent, except at tip; prominence on anteromedial clypeal margin present as an indistinct swelling or undulation; mandible regularly triangular with oblique basal margin; long, curved setae on venter of head capsule present. Mesosoma. Pronotum strongly inclined anteriorly. Erect pronotal setae lacking or very minute (one or two tiny setae may be present). Mesonotum straight. Erect mesonotal setae lacking or very minute (one or two tiny setae present). Mesothoracic spiracles always prominent as small, vertical protuberances; propodeal dorsum protuberant; placement of propodeal spiracle posteriad and near propodeal declivity; propodeal angle present as a bluntly defined right angle, the dorsal and declivitous propodeal faces never separated by a carina. Erect propodeal setae sparse to absent. 'Petiole. 'Dorsum of node planar; node thin, scale-like, orientation more-or-less vertical. Gaster. Non-marginal erect setae of gaster absent on first gastral tergite; marginal erect setae of gaster absent on first tergite. General characters. Allometric differences between workers of same nest absent. Colour head, mesonotum propodeum and legs reddish brown, pronotum orange, gaster dark chocolate.

Measurements. Worker (n = 1)—CI 95; EI 24; EL 0.32; EW 0.18; HL 1.40; HW 1.33; ML 0.55; PpH 0.23; PpL 0.75; SI 77; SL 1.03.