Iridomyrmex fulgens, Heterick & Shattuck, 2011

Heterick, Brian E. & Shattuck, Steve, 2011, Revision of the ant genus Iridomyrmex (Hymenoptera: Formicidae) 2845, Zootaxa 2845 (1), pp. 1-174 : 82-83

Iridomyrmex fulgens sp. n.

( Fig. 36 )

Types. Holotype worker from 1km E Curdimurka , 29°29’S 137°06’E, South Australia, 22 September 1972, J. E. Feehan, ANIC Ants Vial 16.69 ( ANIC, ANIC32-059632 ) . Paratypes: 2 workers, same data as holotype ( ANIC, ANIC32-040922 ) ; 3 workers from c. 36km ESE Curdimurka , 29°36’S 137°26’E, South Australia, 21 September 1972, J. E. Feehan, ANIC Ants Vial 17.70 ( ANIC, ANIC32-040930 ) ; 3 workers from c. 28km S Parachilna , 31°23’S 138°25’E, South Australia, 14 September 1972, J. E. Feehan, ANIC Ants Vial 16.58 ( ANIC, ANIC32- 040929 ) ; 3 workers (one with gaster detached and glued to point) from Curdimurka , South Australia, 2 October 1978, P. J. M. Greenslade ( MCZC, ANIC32-039369 ) ; 2 workers from 50km NE Clifton Hills , South Australia, August 1975, Forrest ( BMNH, ANIC32-039367 ) .

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.

Comments. 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. This is yet another species closely related to I. 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). Workers 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.

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

Figures

FIGURE 36. Iridomyrmex fulgens (Sandringham, Qld, ANIC32-037648): A. Front of head; B. Side of body; C. Top of body; D. Distribution of material examined.