Nelson cave spider  (Spelungula cavernicola)

Although classified as Data Deficient (DD) on the IUCN Red List 2006 due to a lack of sufficient information, this spider is believed to be critically endangered and facing a high risk of extinction in the wild (6). The population size is estimated to number fewer than 250 mature individuals (6), and its rarity and restricted habitat mean that the Nelson cave spider occupies an extremely precarious existence (4). No major threats are known, but minor possible threats include rats, cave usage and disturbance, and the collection of egg sacs by cave visitors (2).

The Nelson cave spider is New Zealand's only spider legally protected by the Wildlife Act 1953 (3).