Diacamma leve

This species is allopatric with the other Australian species of the genus, being found in the Northern Territory while the others occur in Queensland. In the Darwin region this species is restricted to riparian areas associated with the Howard and Daly River systems (A. Andersen, pers. comm.).

Identification
Dorsal surfaces of pronotum and head with at most very fine, indistinct sculpturing. Diacamma leve can be separated from other Australian species by the form of this sculpturing.

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 *  leve. Diacamma australe var. levis Crawley, 1915a: 134 (w.) AUSTRALIA. Junior synonym of australe: Taylor & Brown, D.R. 1985: 29. Revived from synonymy and raised to species: Shattuck & Barnett, 2006: 17.

Taxonomic Notes
Crawley (1915) correctly recognised this taxon as distinct from typical Diacamma australe (the only other described species at that time), although by today's standards it warrants full-specific rather than subspecific status.

There is a trend for the head to be broader for a given head length (as shown by the larger CI values) in this taxon, but some specimens overlap with specimens of all other Australian species, reducing the usefulness of this character. It is possible that the differences in sculpturing are simply geographic variation and this taxon is conspecific with Diacamma schoedli (with which it shares petiolar shape). However, there is currently no indication of intermediate forms or clinal variation in this character and the noted differences are consistent across all available material of both taxa. Thus current material suggests two taxa are involved, rather than a single variable species. The synonymy of this species with Diacamma australe by Taylor & Brown (1985) was not supported by Shattuck (2006).

Description
Measurements (n = 6): HL 2.52 - 2.78 mm, HW 2.15 - 2.38 mm, CI 81 - 87, SL 2.84 - 3.14 mm, SI 129 - 141, ML 3.73 - 4.19 mm, MTL 2.29 - 2.59 mm, PH 1.25 - 1.50 mm, PL 0.98 - 1.06 mm, PI 70 - 84.

References based on Global Ant Biodiversity Informatics

 * Andersen A. N., J. C. Z. Woinarski, and B. Hoffman. 2004. Biogeography of the ant fauna of the Tiwi Islands, in northern Australia's moonsoonal tropics. Australian Journal of Zoology 52: 97-110.
 * Andersen A. N., M. Houadria, M. Berman, and M. van der Geest. Rainforest ants of the Tiwi Islands: a remarkable centr of endemism in Australia's monsoonal tropics. Insectes Sociaux 59: 433-441.
 * Andersen, Alan N., John C.Z. Woinarski and Ben D. Hoffman. 2004. Biogeography of the ant fauna of the Tiwi Islands, in northern Australia's monsoonal tropics. Australian Journal of Zoology 52: 97-110.
 * Shattuck S. O., and N. J. Barnett. 2006. Australian species of the ant genus Diacamma (Hymenoptera: Formicidae). Myrmecologische Nachrichten 8: 13-19.