Description: A lively and fast-moving swimming crab of medium size, with a carapace up to 8 cm across. Brown pubescence gives the crab a velvety appearance, however the carapace is actually coloured dark brown – blue, which shows through on tips of claws. Pincers of equal length, covered in a fine pubescence. Up to ten narrow teeth on frontal margin between the eyes and five pointed teeth on each side of the carapace. Fifth pair of legs are modified to paddles to allow this crab to swim, the paddles have a distinctive lined pattern. Its eyes are bright red, and give this crab one of its other common names of ‘devil crab.’

Habitat: Prefers rocky shores and substrata and more abundant on sheltered sites. Found from lower shore to shallow sublittoral.

Distribution: A very common species around the UK and Ireland.

Similar Species: Unlikely to be confused with any other species.

Key Identification Features:

• Bright red eyes.
• Velvety appearance with some dark blue colouration showing through, especially on tips of claws.
• Fifth pair of legs flattened to paddles bearing distinctive pattern.

Distribution Map from NBN: Necora puber at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Necora puber at iNaturalist World Species Observations database.

WoRMS: Necora puber at World Register of Marine Species. Accepted name: Necora puber (Linnaeus, 1767). AphiaID: 107398.

Classification: Biota; Animalia; Arthropoda; Crustacea; Multicrustacea; Malacostraca; Eumalacostraca; Eucarida; Decapoda; Pleocyemata; Brachyura; Eubrachyura; Heterotremata; Portunoidea; Polybiidae; Necora