Conical shell up to 30mm in length (12mm in height). The shell is white or grey externally, sometimes with darker bands running from the apex to the margin. The inside is also white with coloured rays and a destinctive yellow head scar. The shell surface is sculptured with radial ridges running from the apex to the shell margin. The posterior of shell tends to have an irregular outline.
- Foot is black or blackish brown.
- Pallial (peripheral) tentacles are opaque, chalk- white.
- Patella ulyssiponensis has a pale foot, and opaque white (occasionally orange) pallial tentacles.
- Patella vulgata has a foot that varies from as dark as Patella depressa to as pale as P. ulyssiponensis. P. vulgata has translucent whitish pallial tentacles while the other two have opaque white pallial tentacle (sometimes orange on P. ulyssiponensis)
Found on middle shore, often in pools or trickles from pools where it feeds by grazing material from the rock surface using its radula. Mainly breeds in summer. Eggs are fertilised in the water column and larvae later settles in low shore pools (especially amongst Lithothamnion) and wet areas.
Occurs in south-west Britain from Beachy Head in south-east England to Lleyn Peninsula in North Wales (historically to north-west Anglesey. Absent from Ireland and Scotland, but many false records there based on unreliable exterior of shells. Southwards along Atlantic coasts of Europe to north Africa.