Like many reptiles the Chinese water dragon possesses a small, iridescent, photosensitive spot between their eyes: the pineal eye; or sometimes referred to colloquially as the third eye. It is thought that this helps regulate body temperature.
Chinese water dragons are not a native Hong Kong species, but they are a popular pet, and escaped or released pets have now set up a few breeding colonies in parts of Hong Kong. They can grow up to 1 m in length, including the long tail, and can live up to fifteen years.
Adult males have larger, more triangular heads, and have developed crests on the head, neck and tail.