Iridomyrmex spodipilus

Iridomyrmex spodipilus
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Dolichoderinae
Tribe:	Leptomyrmecini
Genus:	Iridomyrmex
Species:	I. spodipilus
Binomial name
Iridomyrmex spodipilus Shattuck, 1993

Specimens from Fowlers Gap, New South Wales, have been collected in low shrub and grassland, which presumably this ant favours. Otherwise there are no ecological data.

Identification

Iridomyrmex spodipilus is the only southern member of the I. sanguineus complex, and, like Iridomyrmex spadius, also occurs in two disjunct populations. In general appearance, this species strongly resembles a very large Iridomyrmex discors, with which it shares pale, erect setae on its body parts. However, under a microscope its long anteromedian clypeal prominence, its higher scape index and its overall dimensions are sufficient to easily separate it from I. discors. As with I. discors, iridescence is weak to absent in this species, but where it occurs it is pink to purple. In his study of the I. purpureus species-group, Shattuck (1993a) mentions differences between I. spodipilus populations occurring in South Australia and those occurring in Queensland and New South Wales. South Australian workers are lighter in overall colour and head and mesosoma do not vary, whereas eastern workers are darker with the head lighter than the mesosoma. Workers of the latter are also slightly smaller on average than those of the former. Shattuck considered these differences to be intraspecific.

Keys including this Species

• Key to Iridomyrmex species

Distribution

Latitudinal Distribution Pattern

Latitudinal Range: -26.08333333° to -31.81666667°.

North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

• Source: AntMaps

Distribution based on Regional Taxon Lists

Australasian Region: Australia (type locality).

Distribution based on AntMaps

Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.

Nomenclature

The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

• spodipilus. Iridomyrmex spodipilus Shattuck, 1993a: 139, fig. 18 (w.) AUSTRALIA. See also: Heterick & Shattuck, 2011: 141.

Type Material

• Holotype, worker, 21km WNW William Creek, South Australia, Australia, 28°49′0″S 136°09′0″E, Feehan,J.E., ANIC32-009173, Australian National Insect Collection.
• Paratype, 28 workers, 21km WNW William Creek, South Australia, Australia, 28°49′0″S 136°09′0″E, ANIC32-009174, Australian National Insect Collection.
• Paratype, workers, 21km WNW William Creek, South Australia, Australia, 28°49′0″S 136°09′0″E, The Natural History Museum.
• Paratype, workers, 21km WNW William Creek, South Australia, Australia, 28°49′0″S 136°09′0″E, Museum of Comparative Zoology.

Description

Worker Description. Head. Posterior margin of head strongly concave; erect setae on posterior margin in full- face 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 convex; antennal scape surpassing posterior margin of head by 1–2 x its diameter. Erect setae on scape present and abundant; prominence on anteromedial clypeal margin projecting as triangular spur; mandible elongate triangular with oblique basal margin; long, curved setae on venter of head capsule absent. Mesosoma. Pronotum moderately and evenly curved over its length. Erect pronotal setae numerous (12 or more), short and bristly. Mesonotum sinuous. Erect mesonotal setae numerous (12 or more), short and bristly. Mesothoracic spiracles always prominent as small, vertical protuberances; propodeal dorsum protuberant; 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 acuminate; 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 head and mesosoma reddish with very pale blue, greenish or yellow iridescence, legs light brown, gaster black with bluish-green iridescence. Colour of erect setae pale, ashy brown.

Measurements. Worker (n = 25)—CI 86–95; EI 19–24; EL 0.34–0.41; EW 0.18–0.24; HL 1.65–2.07; HW 1.44–1.90; ML 0.74–1.00; PpH 0.23–0.38; PpL 0.75–1.05; SI 87–102; SL 1.48–1.7 1.

References

• Heterick, B.E. & Shattuck, S.O. 2011. Revision of the ant genus Iridomyrmex (Hymenoptera: Formicidae). Zootaxa 2845: 1-175.
• Shattuck, S. O. 1993a. Revision of the Iridomyrmex purpureus species-group (Hymenoptera: Formicidae). Invertebr. Taxon. 7: 113-149 (page 139, fig. 18 worker described)

References based on Global Ant Biodiversity Informatics

• Heterick B. E., and S. Shattuck. 2011. Revision of the ant genus Iridomyrmex (Hymenoptera: Formicidae). Zootaxa 2845: 1-174.
• Shattuck S. O. 1993. Revision of the Iridomyrmex purpureus species-group (Hymenoptera: Formicidae). Invertebrate Taxonomy 7: 113-149.