St Piran’s Hermit Crab

The St Piran’s Hermit Crab is a warm water species and has only recently returned to our shores, predominantly in Cornwall and Devon, following its disappearance in the 1980’s.

Fast Facts

Latin name: Clibanarius erythropus

Notable feature: Red eye stalks with striking black and white eyes.

Conservation Status: Not Evaluated

Where in the UK: South West England

St Piran's Crab © Jack Sewell

The St Piran’s Hermit Crab is a small hermit crab (up to 30mm long) that will inhabit a variety of empty sea snail shells – with a preference for Dog Whelk shells.

Unlike many other hermit crabs in the UK, its claws are equal in size with black tips and will emerge from its shell after its legs.  The St Piran’s has red eye stalks tipped with black and white eyes; its body is reddish-brown in colour with electric blue highlights along its legs, claws and around its mouth parts.

They can be a little shyer than the Common Hermit Crab but are also often seen climbing around the sides of rocks and boulders; even sunbathing on flat surfaces out of the water to dry out their shells!

Found under rocks in the mid and lower shore where they mostly eat algae but will also scavenge for detritus too.

This little crab was named after St Piran – the Patron Saint of Cornwall.  St Piran was an Irishman who was thrown into the sea bound to a heavy granite stone, by his King of the time.  Legend tells that when the stone hit the sea Piran’s bounds were loosed and the stone itself actually floated; carrying Piran from Ireland to the Cornish coast where he made his home.