Iridomyrmex fulgens

Workers of this species have been taken in pitfall traps, and one specimen from Marree, South Australia, was collected from under emu dung, but apart from this there are no ecological data for the species.

Identification
Iridomyrmex fulgens is a brown-to-dark-brown, shiny ant with a uniform morphology throughout its range. The combination of erect setae on antennal scape and hind leg and the mostly smooth sides of the head capsule, when the worker is in full-face view, is unique, and identifies this taxon.

Distribution
This is yet another species closely related to Iridomyrmex rufoniger that has a distribution mainly in drier inland areas, and records come from Queensland, New South Wales and South Australia (the state in which most specimens have been collected).

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 *  fulgens. Iridomyrmex fulgens Heterick & Shattuck, 2011: 82, fig. 36 (w.) AUSTRALIA.

Description
Worker Description. Head. Posterior margin of head weakly concave, or strongly 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, or absent from sides of head in full-face view (one to a few small setae may be present near mandibular insertion). Ocelli absent; in full-face view, eyes set at about 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 convex; antennal scape barely attaining posterior margin of head, or surpassing it by less than 1 x its diameter. Erect setae on scape present and abundant, or present and sparse; prominence on anteromedial clypeal margin present as an indistinct swelling or undulation; mandible triangular with distinct angle between masticatory and basal margins; long, curved setae on venter of head capsule absent. Mesosoma. Pronotum strongly inclined anteriorly, or moderately and evenly curved over its length. Erect pronotal setae numerous (12 or more) and longest setae elongate, flexuous and/or curved. Mesonotum straight, or evenly curved. Erect mesonotal setae moderate in number (6-12), short and bristly. Mesothoracic spiracles always inconspicuous; propodeal dorsum smoothly and evenly convex; placement of propodeal spiracle posteriad and near propodeal declivity, or mesad, more than its diameter away from propodeal declivity; propodeal angle weakly present or absent, the confluence of the dorsal and declivitous propodeal faces indicated, if at all, by an undulation. Erect propodeal setae numerous (12 or more), short and bristly. Petiole. Dorsum of node convex, or planar; node thin, scale-like, orientation more-or-less vertical. Gaster. Non-marginal erect setae of gaster present on first gastral tergite; marginal erect setae of gaster present on first tergite. General characters. Allometric differences between workers of same nest absent. Colour medium brown to dark chocolate, gaster with greenish-yellow to bluish iridescence. Colour of erect setae whitish-yellow.

Measurements. Worker (n = 4)—CI 91–94; EI 26–27; EL 0.18–0.22; EW 0.14–0.17; HFL 0.76–0.94; HL 0.75–0.85; HW 0.68–0.79; ML 0.91–1.06; MTL 0.57–0.67; PpH 0.14–0.17; PpL 0.40–0.44; SI 91–93; SL 0.64– 0.73.

Etymology
Latin: ‘brilliant’ or ‘splendid’, as a reference to the shining brown foreparts and iridescent gaster in this species.