 The terrestrial Argonemertes dendyi is a native of Australia but has been found in the British Isles, in Sao Miguel in the Azores, in Gran Canaria, and in a lava tube cave at Kaumana on the Island of Hawaii. It can build a cocoon, which allows it to avoid desiccation while being transported, and it may be able to build populations quickly in new areas as it is a protandrous hermaphrodite. Another terrestrial genus, Geonemertes, is mostly found in Australasia but has species in the Seychelles, widely across the Indo-Pacific, in Tristan da Cunha in the South Atlantic, in Frankfurt, in the Canary Islands, in Madeira and in the Azores.
