The 13-foot-long 'prehistoric looking' sixgill shark (Hexanchus griseus) was discovered off County Clare on the west coast, at a relatively shallow depth of about 200 feet.

The shark gets its name from the fact that is has six gill slits, unlike most other sharks which have only five.   .

The sixgill shark, sometimes known as the cow shark, is a common species of deep water shark.

They eat on other fish including sharks, skates and rays, bony fish, squid and crabs. .

The sharks live in deep water miles off-shore and as a result this species has little interaction with humans.

They feed on other fish including sharks, skates and rays, bony fish, squid and crabs

'Ireland is the gateway to the Atlantic and we are increasingly amazed at how important Irish waters seem to be for these huge shark and ray species

Sixgill sharks feed on other fish including sharks, skates and rays, bony fish, squid and crabs (stock image)

Earlier this year, a group of British fishermen caught 14 sixgill sharks in a 'secret location' in the north Atlantic dubbed Jurassic Park

There are three species of sixgill sharks, which belong to the genus Hexanchus and are characterised by saw-like lower teeth. 

It was originally thought that the genus comprised of just two species: the bluntnose sixgill shark (Hexanchus griseus) and the bigeye sixgill (Hexanchus nakamurai). 

A newly identified species of sixgill shark, the Atlantic sixgill shark (Hexanchus vitulus), settled the debate as to whether bigeye sixgill sharks from the Atlantic constitute a separate species in February 2018

Bluntnose sixgill shark (Hexanchus griseus): This large, deepwater shark has comb-like, yellow lower teeth, a long tail, and is the largest of the sixgill species, with an average length of 15 to 16 feet (4.6 to 4.9 metres). 

Bigeye sixgill shark (Hexanchus nakamurai): A little-known, moderately large shark up to 5.9 feet (1.8 metres) long

Atlantic sixgill shark (Hexanchus vitulus): Measures up to six feet (1.8 metres) long and lives at extreme ocean depths.