The ant fauna of the Pilbara Bioregion, Western Australia

Abstract

-The ant fauna of the Pilbara Bioregion, which covers an area of ca. 179,000 km 2 , is reviewed. During surveys undertaken between May 2003 and September 2006, ants were one of the taxonomic groups to receive special attention. The total number of ant species recorded from 24 survey areas was 245, and these were placed in 37 genera and 9 subfamilies. Ants recorded from single quadrats ('singletons') accounted for 18.8% of the species. The most speciose genera were Camponotus (36 spp.), Iridomyrmex (31 spp.) and Melophorus (30 spp.). Based on current knowledge, 43% are purely Eremaean, 8% are primarily Bassian, 6% are primarily Torresian, nearly 17% occur over two of Australia's three biogeographic divisions, and 25% are widespread over all three. At a quadrat level, there was no signifi cant correlation between richness and any environmental variable, while clustering analysis revealed weak environmental correlations with ant assemblage composition. The classifi cation at survey area level identifi ed six groupings of ants; three climatic variables associated with these groupings were identifi ed, namely annual temperature, precipitation in the coldest quarter of the year and annual precipitation.

Compositional patterns in terrestrial fauna and wetland flora and fauna across the Pilbara biogeographic region of Western Australia and the representativeness of its conservation reserve system

“…This result is generally consistent with taxon-specifi c analyses of individual species relationships and multivariate analyses of the Pilbara Biodiversity Survey data (Gibson and McKenzie 2009;Burbidge et al 2010;Guthrie et al 2010;Heterick et al 2010;Pinder et al 2010;Volschenk et al 2010;Doughty et al 2011). Among the taxonomic groups examined in these analyses, beetle, scorpion, bird, reptile and ground-mammal patterns all showed strong relationships with soil attributes.…”

“…Similarly the three biotic variables retained in the model, which included the variable that made the fourth largest contribution (woody vegetation cover), are likely to be surrogates for habitat productivity. Climate variables were weakly supported in the taxon-specific analyses, although precipitation variables were shown to marginally influence both ant and spider composition at sub-regional level Heterick et al 2010). The landform variable that made the most contribution to the fi nal model was average topographic wetness which is likely to infl uence habitat productivity and relate to high woody vegetation cover that occurs along riparian zones, foot slopes and other water-gaining environments in the Pilbara.…”

“…The sites were positioned across the geographical extent of the region in a stratified array to sample the main climatic gradients, geological formations, landforms, river catchments, soils and vegetation types. The survey fi ndings, published as a series of papers in a dedicated Supplement of the Records of the Western Australian Museum, describe the relationship between the region's physical environment and components of its biota (Gibson andMcKenzie 2009, McKenzie et al 2009;Burbidge et al 2010;Guthrie et al 2010;Heterick et al 2010;Pinder et al 2010;Volschenk et al 2010;Doughty et al 2011). Each of these taxonspecifi c papers related biodiversity survey data to environmental attributes at the site level.…”

Documenting the terrestrial invertebrate fauna of Barrow Island, Western Australia

“…Also, with the exception of the ants, the taxonomy used in the two regional studies has not been resolved and reconciled, so it is not possible to confidently assess the affinities of the Barrow Island invertebrate fauna with these two regions. However, for ants, of the 103 species sampled on Barrow Island, 47 species are common to the 243 species sampled in the Southern Carnarvon Basin (Gunawardene & Majer 2004) and 79 are common to the 244 species sampled in the Pilbara region (Heterick et al . 2010, in George et al .…”

A taxonomic overview and key to the ants of Barrow Island, Western Australia

“…The taxa themselves are very representative of the broader Eremaean ant fauna, with 93 species shared between Barrow Island and the adjoining mainland. This represents 79.5% of the ants recognised from Barrow Island and 38.0% of the 245 Pilbara ants identified in Heterick et al (2010). By way of contrast, only 52 ant species from Barrow Island (i.e., 44.4% of the total recognized) are included within the 243 species of ants identified by Gunawardene and Majer (2004) from the southern Carnarvon Basin, the latter reflecting a much more temperate fauna.…”