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.
These were found living on Tai Mo Shan. They are considered introduced, rather than invasive, but could have been living here previously and gone extinct.