Description: This flatworm reaches a size of up to 5 cm and has a very distinctive 'candy stripe' colouration. The body is an off-white to cream with many distinctive thin black stripes. There are two tentacles at the head and eyespots should be visible. The body is flat overall but thicker towards the centre with the thin outer edges often forming a frill or curls.

Habitat: Found from the intertidal down to 20 m or more. Normally found amongst the ascidian Clavelina lepadiformis on which it prefers to feed, or other animal turf, on boulders or wrecks. Can also occasionally be seen travelling on seabed, or under boulders in the intertidal.

Distribution: Found on all coasts of Britain and Ireland aside from the east coast of Scotland and England.

Similar Species: Unlikely to be confused with any other species. Colour and body shape are distinctive.

Key Identification Features:

• Flat body up to 5 cm in length.
• Often the outer edges are form a frill or are curled/ruffled.
• Off-white to cream body with black striping, giving a distinctive 'candy stripe' look.

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

iNaturalist: Prostheceraeus vittatus at iNaturalist World Species Observations database.

GBIF data for Prostheceraeus vittatus

WoRMS: Prostheceraeus vittatus at World Register of Marine Species. Accepted name: Prostheceraeus vittatus (Montagu, 1815). AphiaID: 142820.

Classification: Biota; Animalia; Platyhelminthes; Rhabditophora; Polycladida; Cotylea; Euryleptidae; Prostheceraeus