Epopostruma inornata, Shattuck, S. O., 2007

Shattuck, S. O., 2007, New species of myrmicine ants from Western Australia (Hymenoptera: Formicidae)., Zootaxa 1661, pp. 47-53 : 48-50

Epopostruma inornata new species

(Figs 1-4)

Description: Holotype worker. TL 2.8, HL 0.67, HW 0.57, CI 85, MandL 0.30, MandI 45, SL 0.33, SI 58, PW 0.41, ML 0.75. In full face view lateral margin of head between eye and posterior corner forming a gentle convexity. Pronotal spines absent, anterolateral corners of pronotum very slightly angular. Posterior section of metanotum in approximately same plane as dorsal face of propodeum, junction of these plates indistinct. Posterior face of propodeum between bases of spines and propodeal lobes with thin flanges. Petiolar spines reduced to a small protuberance or angle. Anterior face of postpetiole shorter than dorsal face and separated from it by a broadly rounded angle; lateral surface of postpetiole approximately vertical and rounding gradually from dorsal to posterior surfaces, in dorsal view lateral margins parallel. Dorsum of petiole, postpetiole and gaster with short, appressed hairs. First gastral tergite smooth. Body colour yellowish brown, dorsum of head and gaster slightly darker, mandibles and legs lighter.

Material examined: Holotype worker from Western Australia, Karragullen (misspelled as “Karagullen” on the label, located at 32°06'S 116°07'E), 1978 (J. D. Majer) ( ANIC, No. 32-007280 ) .

Comments: This rare species is currently known from a single specimen. It belongs to the quadrispinosa species group of Shattuck (2000), and is one of only two members of this group to occur west of the Adelaide region (the other being E. quadrispinosa ). Epopostruma inornata can be separated from other species in this genus by the presence of the following characters:

In full face view the lateral margin of the head between the eye and the posterior corner forming a gentle convexity.

Humeral angles of pronotum rounded, lacking spines.

Dorsum of petiole lacking elongate spines.

Anterior face of postpetiole shorter than the dorsal and posterior faces.

Sides of postpetiole approximately vertical and rounding gradually from dorsal to posterior surfaces.

In dorsal view the postpetiole lacking lateral teeth.

The following modifications to the key provided by Shattuck (2000) will allow the identification of this species.

12. In dorsal view the posterolateral teeth of the postpetiole wider than the anterolateral teeth..... areosylva

In dorsal view the postpetiole either lacking lateral teeth, or when present, anterolateral and posterolateral teeth approximately the same width............................................................................................12A

12A. Dorsum of petiole armed with lateral angles .............................................................................. inornata

Dorsum of petiole armed with distinct spines .......................................................................................13