Diacamma australe

Diacamma australe is found along the northern Queensland coast and is sympatric with Diacamma schoedli in the northern part of its range.

Identification
Dorsal surfaces of pronotum and head with distinct rugae. Petiolar spines relatively widely spaced, anterior face of node shorter than dorsal face and separated from it by a distinct angle.

This species can be separated from Diacamma colosseense and Diacamma schoedli by the presence of a block-like petiolar node and distinct sculpturing on the first gastral tergite. Note that this tergite is sculptured in all of these species. However, in this species the sculpturing is stronger and covers the posterior two-thirds of the segment, while in the others the sculpturing is weaker and limited to the anterior half.

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 *  australe. Formica australis Fabricius, 1775: 393 (w.) AUSTRALIA. Forel, 1915b: 26 (m.); Wheeler, G.C. & Wheeler, J. 1952c: 609 (l.). Combination in Diacamma: Mayr, 1862: 718. See also: Shattuck & Barnett, 2006: 14.

Description
Measurements (n = 12): HL 2.55 - 2.88 mm, HW 2.06 - 2.35 mm, CI 77 - 84, SL 2.87 - 3.27 mm, SI 133 - 148, ML 3.67 - 4.12 mm, MTL 2.34 - 2.65 mm, PH 1.26 - 1.59 mm, PL 0.95 - 1.14 mm, PI 66 - 79.

References based on Global Ant Biodiversity Informatics

 * Emery, C.. "Catalogo delle formiche esistenti nelle collezioni del Museo Civico di Genova. Parte terza. Formiche della regione Indo-Malese e dell'Australia (continuazione e fine)." Annali del Museo Civico di Storia Naturale Giacomo Doria (Genova) (2) 5, no. 25 (1887): 427-473.
 * Forel A. 1915. Results of Dr. E. Mjöbergs Swedish Scientific Expeditions to Australia 1910-13. 2. Ameisen. Ark. Zool. 9(16): 1-119
 * Shattuck S. O., and N. J. Barnett. 2006. Australian species of the ant genus Diacamma (Hymenoptera: Formicidae). Myrmecologische Nachrichten 8: 13-19.
 * Viehmeyer H. 1914. Papuanische Ameisen. Deutsche Entomologische Zeitschrift 1914: 515-535.