Why do the other Gondwana connected lands have cichlids and Australia does not?
A simple answer is that Australia’s freshwater fishes became separated from the rest of Gondwanaland before the cichlids developed in the rest of what was formerly one continent. The Rainbowfish developed within Australasia after the land masses separated. That makes the presence of Rainbow Fish and the absence of cichlids a uniquely Australian feature. That development probably began during the Eocene Epoch. During that time, Australia was close to Antarctica and the cichlid homelands were warmer places that developed new forests and new animal species that did not develop in Australia and Antarctica.
