An extinct marsupial lion had a unique and savage hunting style, using its teeth to restrain a victim before ripping it apart with huge thumb claws, research suggests.

The strategy is the opposite of that used by present day lions, which hold prey with their claws before delivering a killing bite.

Thylacoleo carnifex lived in Australia up to a few tens of thousands of years ago and was about the size of a large jaguar.

The creature is depicted in native Australian cave art and some speculate it may still survive as the mythical "Queensland Tiger".

A key feature of the animal was a very large claw on the thumb of each forepaw, similar but much bigger than a cat's "dewclaw".

Scientists who studied Thylacoleo bone structure found that it had a highly unusual elbow joint. It suggested a lot of rotational ability - similar to that seen in a tree-climbing animal - combined with features normally seen in ground-dwellers.

At the same time the animal's incisors were blunt, making them better suited to gripping flesh rather than piercing.

The researchers concluded that, unlike any living predator, the marsupial lion held prey with its teeth and killed with its claws.

Lead scientist Dr Christine Janis, from the University of Bristol, said: "If Thylacoleo had hunted like a lion using its forelimbs to manipulate its prey, then its elbow joint should have been lion-like.

"But, surprisingly, it a unique elbow joint among living predatory mammals - one that suggested a great deal of rotational capacity of the hand, like an arboreal mammal, but also features not seen in living climbers, that would have stabilised the limb on the ground, suggesting that it was not simply a climber."

The findings are published in the journal Paleobiology.