A team of international scientists has discovered the fossilized remains of an ancient crocodile with mammal-like teeth in Tanzania, southwest Africa.
The team led by Ohio University in the US says the crocodile is about the size of a cat, and probably lived in the mid-Cretaceous period, some 100 million years ago.
The animal has molar-like teeth as well as sharply pointed front teeth, putting it closer to a mammal than modern reptiles.
The scientists believe it lived on land in the southern hemisphere and fed on insects and other small animals before mammals thrived.
Chief researcher at Japan's National Museum of Nature and Science, Yukimitsu Tomida, says a variety of crocodiles are believed to have lived on land and in the sea at that time.
He said the discovery is interesting as it shows the animal evolved differently from the way researchers had previously thought.
The find will be published in the British journal Nature to be issued on Thursday.