A 90-million-year-old fossil of an unknown species of crocodile that inhabited Brazil's southeast region in unusual environmental conditions has been unveiled by researchers in Rio de Janeiro.

Brazilian paleontologists presented a fossil of an unknown species of a prehistoric crocodile, which roamed Brazil's southeastern region some 90 million years ago.

Ismar Carvalho, paleontologist said, "This species of Aramdillosuchus is only found in the inland region of Sao Paulo state and this has been a surprise, especially because we are used to finding crocodiles in hot and humid areas, but in this case these are crocodiles who lived in hot, arid and dry regions."

The 2-meter-long crocodile that weighed some 120 kilograms, lived in the late Cretaceous period. Then, the average day-time temperature in Brazil's southeast was 45 degrees Celsius.

Although only fragments of the fossil were unearthed, researchers of Rio de Janeiro's Federal University managed to assemble the crocodile's complete skeleton.

Researches also said the new species, found in Sao Paulo state's Bauru basin region, had unique techniques to escape larger predators.