Charopidae is a highly speciose family of land snails mostly distributed in the main landmasses and archipelagos of the Southern Hemisphere, with a few genera in the Northern Hemisphere. DNA sequencing is making substantial contributions to understanding the phylogeography of Charopidae and the systematic relationships of its subfamilies and related families in the Punctoidea. Here, new data from 28S rRNA are combined with available GenBank sequences to investigate whether Australian Charopidae comprise a single clade, exclusive of species from other regions. Phylogenetic analyses show that this is not the case, with most species from Australia and other regions included in a bootstrap-supported clade that excludes some Australian species. Analyses of concatenated 28S rRNA data and available cytochrome c oxidase subunit I (COI) also contradicted monophyly of Australian species, as did analyses of inferred COI protein sequences. In DNA analyses, the genus Hirasea and Australian taxa with an incomplete secondary ureter were basal within Charopidae. We also examined whether known doubts about the taxonomic status of supra-generic clades in Punctoidea could be resolved by considering autapomorphic COI amino acid changes. Such variation could not generally be applied as an objective criterion for taxonomic categorization but did identify some clades for taxonomic investigation.
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