The lesser stick-nest rat or white-tipped stick-nest rat (Leporillus apicalis) is an extinct species of rodent in the family Muridae. It lived in central Australia where it built nests of sticks that accumulate over years and can become very large. The last confirmed sighting of this rat was in 1933 although there is a credible report of a sighting in 1970. In 2008, the International Union for Conservation of Nature listed it as "critically endangered", suggesting that it may yet survive in remote areas of unsurveyed territory, but revised its evaluation to "extinct" again in 2016, based on an assessment in 2012. There is a possibility that a lesser stick-nest rat was seen in a cave in Western Australia in 1970.
The last specimen was found at Mount Crombie.
Conservation status assessment
The 2008 release of the updated IUCN status for the lesser stick-nest rat downgraded the conservation status from extinct to critically endangered (possibly extinct), owing to the very slight possibility that a very small population may still exist in yet to be surveyed remote lands of the Australian interior. This was based on a reliable record from 1970, continued occasional reports of fresh vegetation being added to old stick-nests, and much of this species' range being in remote portions of central Australia which have not yet been fully surveyed. However, the classification was revised to "extinct" again in 2016.