Description: The body is translucent white in colour with opaque white pigment on the tips of the oral tentacles, rhinophores and tail. The cerata are filled with red digestive gland and are capped with white pigment extending right over the tips, instead of forming rings as is usual in other species. Typically about 30mm in length when fully grown.

Habitat: An uncommon species breeding in early summer in sites which are sheltered from wave action but exposed to tidal streams. The normal food is the hydroid Eudendrium arbuscula but other Eudendrium species may be eaten. The spawn consists of a thread which is laid in a wavy spiral coiled amongst the food and on nearby rocks.

Distribution: A northern species in the British Isles, occurring round Scotland and in the Irish Sea, but apparently absent from the western coasts of Ireland and England. There is a single recent record confirmed by a specimen from Lough Hyne, Co Cork. Further distribution includes Norway and the Atlantic coast of America.

Key Identification Features:

• Long cerata of fairly even size giving a shaggy appearance.
• White caps covering the tips of the cerata.

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

iNaturalist: Flabellina pellucida at iNaturalist World Species Observations database.

WoRMS: Flabellina pellucida at World Register of Marine Species. Accepted name: Carronella pellucida (Alder & Hancock, 1843). AphiaID: 1048787.

Classification: Biota; Animalia; Mollusca; Gastropoda; Heterobranchia; Euthyneura; Ringipleura; Nudipleura; Nudibranchia; Cladobranchia; Aeolidioidea; Flabellinidae; Flabellina