Description: The dog whelk is a common species on rocky shores in Ireland and the UK. It's usually around 3 cm tall x 2 cm wide. The colour is variable but often cream to grey-white. It has a heavy shell with 5 large whorls. In adult animals the outer lip of the shell is thick and toothed. There is a short canal-like groove running from the base of the aperture to the outer shell margin.

Habitat: On rocky shores beneath boulders and in tidal rapids, from mid to low shore. Feeds on barnacles so is usually present where these are abundant.

Similar Species: Could be confused with Littorina saxatilis when juvenile, however the siphonal canal on the underside of the shell is characteristic for the dog whelk.

Key Identification Features:

• Heavy shell with 5 thick whorls.
• Siphonal canal on underside of shell.

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

iNaturalist: Nucella lapillus at iNaturalist World Species Observations database.

GBIF data for Nucella lapillus

WoRMS: Nucella lapillus at World Register of Marine Species. Accepted name: Nucella lapillus (Linnaeus, 1758). AphiaID: 140403.

Classification: Biota; Animalia; Mollusca; Gastropoda; Caenogastropoda; Neogastropoda; Muricoidea; Muricidae; Ocenebrinae; Nucella