Description: This periwinkle is up to 1 cm in height and colour can vary, ranging from yellow, red or brown to olive green and sometimes has a banded pattern. The spire is of the shell is flattened, and there is a large opening. The body whorl is slightly larger than the shell opening.

Habitat: Usually found on seaweeds, especially bladder wrack and egg wrack. Usually from mid to lower shore.

Distribution: Found on all coasts of Britain and Ireland.

Similar Species: Could be confused with Littorina fabalis, however in L. fabalis the shell opening is larger than the body whorl, and the spire is flatter.

Key Identification Features:

• Shell opening slighly smaller than body whorl.
• Usually found on bladderwrack and egg wrack.

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

iNaturalist: Littorina obtusata at iNaturalist World Species Observations database.

GBIF data for Littorina obtusata

WoRMS: Littorina obtusata at World Register of Marine Species. Accepted name: Littorina obtusata (Linnaeus, 1758). AphiaID: 140263.

Classification: Biota; Animalia; Mollusca; Gastropoda; Caenogastropoda; Littorinimorpha; Littorinoidea; Littorinidae; Littorininae; Littorina