Appendix A - NT Survey Specimens

The MacDonnell Ranges bioregion in the southern Northern Territory is a centre of land snail endemism in arid Australia, and a high proportion of species are listed as threatened under Northern Territory legislation. We sought to locate extant populations of two endemic and threatened land snails, each known only from a single location. We recorded the first live individuals of the charopid Tateropa aemula at Penny Springs in Watarrka National Park since the type material was collected 131 years ago. We did not detect this species at other spring sites in this national park. We also located the camaenid Divellomelon hillieri alive at one of two sites where it was previously recorded in Palm Valley, Finke Gorge National Park. The total area of occupancy at this site was ~0.6 hectares. Excluding wildfire from the habitat of both species through strategic fire breaks is a high priority, as well as removal of invasive buffel grass at the D. hillieri site. We recommend that an updated conservation assessment is undertaken for T. aemula based on current knowledge of its distribution and threats. Further targeted survey should be undertaken for D. hillieri before undertaking a revised conservation assessment. We also report on other land snail species recorded during our surveys at both national parks.澳大利亚北部领地（Northern Territory）南部的麦克唐奈山脉生物区（MacDonnell Ranges bioregion）是澳大利亚干旱地区陆生蜗牛特有种的分布中心，且有极高比例的物种被依据北部领地相关立法列为受威胁物种。本研究旨在定位两种仅知分布于单一地点的特有受威胁陆生蜗牛的现存种群：我们首次在沃特卡卡国家公园（Watarrka National Park）的彭尼泉（Penny Springs）记录到了炭角螺科（Charopidae）物种*Tateropa aemula*的活体个体——该物种的模式标本已于131年前采集完成——且未在该国家公园的其他泉水点位发现该物种；我们还在芬克峡谷国家公园（Finke Gorge National Park）的棕榈谷（Palm Valley）——该物种此前仅被记录有两个分布点位之一——中发现了坚齿螺科（Camaenidae）物种*Divellomelon hillieri*的活体个体，该点位的实际占用总面积约为0.6公顷。通过设置战略性防火隔离带阻断野火波及这两个物种的栖息地，以及在*D. hillieri*的分布点位移除入侵性Buffel草（Buffel grass），均为当前的高优先级保护措施；我们建议基于当前对*Tateropa aemula*分布与威胁因素的认知，对其开展更新版的保护等级评估，同时建议在对*Divellomelon hillieri*开展修订版保护等级评估前，针对其开展进一步的靶向调查。本研究同时报告了在这两座国家公园的调查过程中记录到的其他陆生蜗牛物种。