'Freaky' Ghostshark discovered with sexual organ on its head



Experts have discovered a new strange species of ghostshark... that has a sexual organ on its head.

The bizarre looking creatures are a type of chimaera - an ancient and bizarre group of fishes distantly related to sharks. Found in deep waters off the Californian coast, the males have a sexual organ on their foreheads known as a tentaculum.

The ghostshark is found in deep waters off the coast of southern California

The new species, the Eastern Pacific black ghostshark (Hydrolagus melanophasma), was described in the international journal Zootaxa.

'It’s a big weird looking freaky thing,' said co-author Doug Long of the California Academy of Sciences.

'They have this club on the top of their head with spikes. People think it’s used for mating.

'It’s like a little mace with little spikes and hooks and it fits into their forehead. It’s jointed and it comes out. We’re not sure if it is used to stimulate the female or hold the female closer.'

Experts believe the 3ft male has a sexual organ on its head

Specimens of the 3ft long fish have been found since the 1960s, but it ended up nameless in museum collections around the world.



It wasn't until an American team precisely measured a pickled example of the blackish-purple fish that it was recognised as its own species.

Chimaeras were once a very diverse and abundant group, as illustrated by their global presence in the fossil record.



Their closest living relatives are sharks, but their evolutionary lineage branched off from sharks nearly 400 million years ago, and they have remained an isolated group ever since.

They survived through the age of dinosaurs mostly unchanged, but today these fishes are relatively scarce and are usually confined to deep ocean waters, where they have largely avoided the reach of explorers and remained poorly known to science.

This new species belongs to the genus Hydrolagus, Latin for 'water rabbit' because of its grinding tooth plates reminiscent of a rabbit's incisor teeth.



Renewed exploration of the world's deep oceans and more extensive analysis of chimaera specimens in museum collections have led to a boom in the number of new chimaera species discovered worldwide in the last decade.