Iridomyrmex nudipes, Heterick & Shattuck, 2011

Heterick, Brian E. & Shattuck, Steve, 2011, Revision of the ant genus Iridomyrmex (Hymenoptera: Formicidae) 2845, Zootaxa 2845 (1), pp. 1-174 : 113-115

Iridomyrmex nudipes sp. n.

( Fig. 57 )

Types. Holotype worker from Lake Wyangan bank, Griffith , New South Wales, 17 July 1979, B. B. Lowery, 10am foragers on mallee stem ( ANIC, ANIC32-040009 ) . Paratypes: 6 workers, same data as holotype ( ANIC, 2 workers;

BMNH, 2 workers ; MCZC, 2 workers); 1 worker from Moonarie, 10km S of Homestead, Gawler Ranges , South Australia, October 1972, P. J. M. Greenslade ( ANIC, ANIC32-042660 ) .

Worker Description. Head. Posterior margin of head weakly concave; erect setae on posterior margin in fullface view set in a row; sides of head noticeably convex; erect genal setae 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 semi-circular. Frontal carinae concave; antennal scape barely attaining posterior margin of head, or surpassing it by less than 1 x its diameter. 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 moderately and evenly curved over its length. Erect pronotal setae moderate in number to numerous (6 or more) and longest setae elongate, flexuous and/or curved. Mesonotum straight. Erect mesonotal setae numerous (12 or more), short and bristly. Mesothoracic spiracles always inconspicuous; propodeal dorsum protuberant; placement of propodeal spiracle posteriad and near propodeal declivity, or mesad, more than its diameter away from 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 numerous (12 or more) and elongate, flexuous and/or curved, or numerous (12 or more), short and bristly. Petiole. Dorsum of node convex; node thick, 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 frons and legs tawny orange to brown, mesosoma orange to brick-red, gaster brown. Colour of erect setae yellow.

Measurements. Worker (n = 4)—CI 95–97; EI 26–28; EL 0.26–0.27; EW 0.20–0.22; HFL 1.04–1.13; HL 0.99–1.06; HW 0.95–1.02; ML 1.37–1.47; MTL 0.80–0.86; PpH 0.24–0.27; PpL 0.52–0.59; SI 82–83; SL 0.79– 0.84.

Comments. Iridomyrmex nudipes is a fairly nondescript member of the viridigaster complex that can be identified by its lack of erect setae on the hind tibiae and its thickish node. The known distribution of the species includes New South Wales and South Australia. This ant is a diurnal forager: workers near Griffith, New South Wales, were collected from mallee stems during mid-morning (10 am).

Etymology. Latin: ‘ nudus ’ ‘naked’ plus ‘ pes ’ ‘foot’.

Figures

FIGURE 57. Iridomyrmex nudipes, pale form (holotype, Griffith, NSW, ANIC32-040009): A. Front of head; B. Side of body; C. Top of body. Iridomyrmex nudipes, dark form (46km E Norseman, WA, ANIC32- 32-031872): D. Front of head; E. Side of body; F. Top of body; G. Distribution of material examined.