Water dragons are native to the Southeast Asian mainland and Indo-Australian archipelago.
Most imports arrive from Thailand or southern China.
Males develop larger heads, jowls and crest on the back of the neck, and their femoral pores are somewhat larger than on the female. You need a large enclosure. The reason most are missing much of their faces, rubbed off from the snout back past the front teeth, is that they will literally rub their flesh off trying to get out of a too small enclosure. Green and Australian can be kept together, with one to three males in a room-sized enclosure. You must monitor to assure all are feeding and basking properly.