Description: The body is greyish-white and speckled with brown or green pigment. The cerata are few in number and cigar-shaped. The rhinophoral and oral tentacles have a sub-terminal ring of white pigment and lower down, towards their base, 1 or sometimes 2 bands of brown pigment. Adults may grow to 10 mm in length.

Habitat: Reported to feed on shallow water hydroids such as Obelia, Hydrallmania and Laomedea. Often found in large numbers forming mixed populations with Tergipes tergipes feeding on Obelia geniculata on kelp fronds. The spawn consists of lozenge-shaped lumps.

Distribution: Found all around the British Isles. Confusion with Nudibranchus scintillans means records prior to 2022 include that species.

Key Identification Features:

• Cerata few in number, cigar-shaped.
• Green pigment patches on body and on cerata.

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

iNaturalist: Nudibranchus exiguus at iNaturalist World Species Observations database.

GBIF data for Nudibranchus exiguus

WoRMS: Nudibranchus exiguus at World Register of Marine Species. Accepted name: Nudibranchus exiguus (Alder & Hancock, 1848). AphiaID: 827532.

Classification: Biota; Animalia; Mollusca; Gastropoda; Heterobranchia; Euthyneura; Ringipleura; Nudipleura; Nudibranchia; Aeolidina; Fionoidea; Eubranchidae; Nudibranchus