A. arafura is known from inland, freshwater habitats in southern Papua New Guinea, northern Australia and Indonesia (southernWest Papua Province; Cogger 1994). Its presence is not confirmed from the east coast of Cape York (K. Sanders pers. comm. 2008). In Indonesian New Guinea it is found as far west as Merauke (K. Sanders and Mumpuni pers. comm.) and Mimika and Lorentz Rivers (O'Shea 1996). The geographic distributions expand in the wet season in Australia (Shine and Lambeck 1985).