Long live the King River Perchlet (Nannatherina balstoni)

摘要: Exactly 100 years following the discovery of Balston’s Pygmy Perch (Nannatherina balstoni) and its subsequent description from south-western Australia, it was added to Australian Government’s endangered species list due a contraction range low abundance relative sympatric species. The current study aimed determine historical contemporary geographical species, quantify reduction prioritise areas for ongoing monitoring management. original common name this King River Perchlet, derived type locality two syntypes deposited at British Museum Natural History. Only one syntype remains. Based on review published information unpublished data held by authors, apparent area occurrence N. balstoni is now ~69% distribution. remaining represents only known specimen that system no longer occur there. Similarly, appears have been extirpated Moore northern limit during latter part 20th century, presumably also many rivers Swan Coastal Plain as well Turner Brook in extreme corner range. genetic differences between populations, proposed loss these populations likely resulted an irreversible evolutionary significant units. A recovery plan critical management with on-ground surveys required order confirm population viabilities. Quantification numerous threats (e.g. impacts instream barriers, surface flow groundwater reductions climate change water extraction, riparian degradation, secondary salinisation presence introduced species) required.