Biogeographic regionalization of Australia: assigning conservation priorities based on endemic freshwater crayfish phylogenetics

There are many methods available for evaluating conservation priorities. Tr aditional methods of species richness, genus richness and critical species counts were compared with newer methods of phylogenetic and genetic diversi ty. Conservation priorities for areas designated by the Interim biogeograph ic regionalisation for Australia (Thackway Br Cresswell, 1995) were assesse d on the basis of the freshwater crayfish fauna of Australia. Distributions for all crayfish species were taken from the literature, and plotted in th e IBRA areas. Species and genus richness, as well as the number of rare or endangered species were calculated for each area. A phylogeny of 35 represe ntative crayfish based on 16 S rDNA sequence data was used to assess phylog enetic and genetic diversity of species and genera. Methods of species rich ness and phylogenetic diversity agreed to a large extent in their ranking o f areas, both methods agreed that the north-west coast of Tasmania and the south-eastern portion of the continent were of highest priority for conserv ing the greatest amount of diversity. These results differ greatly from hig h priority areas based on other taxonomic groups, emphasizing the importanc e of broad taxonomic and ecological sampling in making conservation decisio ns.