A mystery shark with sharp overbite teeth and large bulging eyes was caught by a fisherman in Australia.

The bizarre deep-sea creature baffled trawler Trapman Bermagui when he reeled it from under 2,133ft-deep underwater while fishing off the coast of Sydney on September 12.

It had alien-like features, including enormous eyeballs, a pointy nose, and a striking mouth with an upper and lower set of teeth protruding in a scary smile. At the same time, its body was covered off in thick, rough, leathery skin.

The sea monster remained unidentified as the seasoned fisherman could not pinpoint it.

Fisherman Trapman said: ‘Totally not a cookie cutter. It's a rough skin shark, also known as a species of endeavour dog shark.

‘These sharks are common in depths greater than 600 meters. We catch them in the wintertime usually.'

Scientists were also unsure what the deep-sea creature could be as its unusual characteristics.

Florida State University Coastal and Marine Laboratory associate director of research Dean Grubbs said the species appears to be a rough skin dogfish.

He said: ‘In my deep-sea research, we have caught quite a few of them in the Gulf of Mexico and in the Bahamas. They are in the family Somniosidae, the Sleeper Sharks, the same family of the Greenland Shark, but obviously a much smaller species.'

However, California State University Long Beach Shark Lab professor and director Christopher Lowe thinks it was a kite fin shark.

He said: ‘Looks to me like a deepwater kitefin shark, which are known in the waters off Australia.'

It remained unclear what the creature was while the fisherman reportedly threw it back out to the sea.