A rare two-headed baby timber rattlesnake has been found in a forest in the US state of New Jersey.
The reptile, named Double Dave, was spotted last month and taken by an environmental group.
Joined at the body, the baby venomous snake has two fully-formed heads, four eyes and two flickering tongues – which work independently of each other.
“It would be pretty difficult for this snake to survive in the wild,” environmentalist Dave Schneider said.
He said the snake stiffens when trying to escape, and it would have been an easy catch for predators.
Mr Schneider from Herpetological Associates (HA), a consultancy specialising in the study of endangered and threatened reptiles and amphibians, said he and his colleague spotted Double Dave on 25 August in the Pine Barrens forested area.
This happened as they were observing a rattlesnake giving birth.
Two-headed snakes are usually born the same way as conjoined twins: a developing embryo begins to split into identical twins – but then stops part way.
They came up with the name Double Dave because Mr Schneider and his colleague are both called David.
Mr Schneider told the BBC a special permit had been obtained from the state authorities for HA to keep and study the rare snake.
“We’ll take care of it,” he said.