Research project: Australia’s land snail hotspot: Evolution and Systematics of the Kimberley Camaenidae
- Start date:
- End date:
The Camaenidae arguably are Australia’s most diverse land snail group. They occur in a wide range of habitats, from rainforests to near deserts, with a variety of life styles from arboreal to burrowing. The group encompasses more than 500 species in about 100 genera; the diversity being highest in the tropics and the current classification rests predominantly on morphological revisions.
Australian Museum research has revealed a diverse camaenid radiation in the north-western Australian Kimberley region. Out of 170 species previously studied, 120 were found to be new. This almost quadrupled the number of species known from the Kimberley; an increase that equals or exceeds other spectacular discoveries of new species world wide. A total of 180 camaenid species are currently known from the Kimberley. Extrapolating the proportion of recent discoveries to the scale of the entire region prompts an estimate of about 600 species to occur in the Kimberley - and this project will aim at describing a considerable proportion of these species. Worldwide, there are few regions of comparable size that harbour a similarly diverse land snail fauna, such as New Zealand (1,350 species), Japan (860 species) and Hawaii (800 species). Among all other land snail hotspots, the Kimberley is unique because vast parts of its environment are rather inhospitable for snails. In addition, only one group accounts for the majority of species - the Camaenidae.
Resolved phylogenetic relationships are prerequisite for the understanding of spatial and temporal evolutionary patterns and form the basis for a sound systematisation. A molecular phylogeny of the camaenids from offshore islands, which were previously studied as part of the Kimberley Island Survey conducted from 2008 to 2010, has uncovered vast parallelism in shell forms. This parallelism has caused considerable taxonomic confusion. However, previous work also highlighted the potential of molecular-based approaches to solve the taxonomic problems related to shell parallelism and to open new avenues for the study of diversification and adaptation. In the Kimberley, camaenids typically have micro-ranges, being restricted to small islands of forests where they occur as local endemics.
For their large diversity and narrow-range endemism, camaenid snails are being increasingly recognised as a priority group in conservation. They are suitable surrogates for the overall diversity of terrestrial invertebrate faunas. Hence, there will be a growing need for reliable species identifications for conservation purposes and in environmental consulting particularly in Western Australia. While shells are not always reliable means for taxon identification, species typically are separated by large interspecific genetic distances. The project wants to biuld a comprehensive barcode library to assist reliable and efficient species identifications in the future.
Dr Frank Köhler , Research Scientist