Mekosuchinae

Mekosuchinae was a subfamily of crocodiles from Australia and the South Pacific that have now become extinct. They first appear in the fossil record in the Eocene in Australia, and survived until the Pleistocene in Australia and until the arrival of humans in the Pacific islands of Fiji, New Caledonia and Vanuatu. There is however disagreement on whether or not Mekosuchinae is a subfamily within Crocodylidae, or a distinct family, Mekosuchidae, on its own within the superfamily Crocodyloidea.

Mekosuchine crocodiles were a diverse group. An early species, from Riversleigh Queensland, called Trilophosuchus rackhami, was a short snouted large eyed species that has been nicknamed the 'drop croc' as it is hypothesised it may have attacked prey by climbing trees and dropping on them. The early Miocene species, Harpacochampsa camfieldensis, may have resembled a false gharial. Another mekosuchine fossil, currently undescribed, has been found in Miocene deposits from New Zealand. One genus, Mekosuchus, managed to spread to the islands of the Pacific; it is believed to have island-hopped across the Coral Sea, moving first to a now submerged island known as Greater Chesterfield Island, then New Caledonia and onwards.

Mekosuchines became extinct in Australia after the arrival of crocodiles from the genus Crocodylus, today represented by the Saltwater Crocodile. The group survived on Vanuatu and New Caledonia until the arrival of people, who are presumed to have driven them to extinction.