Description: The tentacles of this sea cucumber are found emerging from coarse gravel or maerl. They are white in colour flecked with varying amounts of brown, so that some individuals may appear brown in colour. The body is long and tapering with five rows of tube-feet. There are two concentric rings of ten tentacles; an outer ring of five pairs of large ones and an inner ring of five pairs of small ones. The spicules are numerous and consist of tables with a perforated disc and central spire. Typically 25cm in length, tentacles about 10 cm.

Habitat: Lives in coarse mobile gravel or maerl usually in fairly strong tidal streams. Dense populations are found in suitable habitats and have periodic behaviour, all disappearing below the surface for hours at a time.

Distribution: Found on southern, western and northeastern coasts of the British Isles. Further distribution includes the Faeroes.

Similar Species: The only holothurian likely to be found in coarse gravel.

Key Identification Features:

• White tentacles flecked with brown.
• Habitat in coarse gravel.
• 10 large and 10 small tentacles.

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

iNaturalist: Neopentadactyla mixta at iNaturalist World Species Observations database.

WoRMS: Neopentadactyla mixta at World Register of Marine Species. Accepted name: Neopentadactyla mixta (Östergren, 1898) Deichmann, 1944. AphiaID: 124685.

Classification: Biota; Animalia; Echinodermata; Echinozoa; Holothuroidea; Actinopoda; Dendrochirotida; Phyllophoridae; Neopentadactyla