Distribution: Madagascar, Egypt and central Africa, south to Namibia, Botswana and Zimbabwe.
Habitat: Mainly large rivers, lakes, waterholes and wetlands; also estuaries and mangrove swamps.
Size: Average 3.5m, but up to 5.5m.
Description: A long body armoured with bony plates set in the skin of the back; long deep-sided tail, short limbs and long-snouted skull.
Lifespan: Ages of over 56 years have been recorded. Estimated to live 70 - 100 years.
Diet: Mammals, birds, reptiles, fish and carrion.
There are between 5 000 - 6 000 species of reptiles in the world today, and of these 23 are crocodilians. One family of crocodilians includes the crocodiles, alligators and caimans - Crocodylidae; the second family, Gavialidae, has only one member - the gharial or gavial (a very narrow-snouted crocodile).
Crocodilians are the closest surviving relatives of the great dinosaurs and they have changed very little during the 150 million years that they have lived on Earth!Read More: Alligator or crocodile? What is the difference?