Black-footed Limpet

Patella depressa

• Most common form of limpet in southern waters
• Strongly ridged shell up to 3cm
• Generally grey in colour
• Found on all wave-exposed rocky shores
• Easily confused with other species such as Patella vulgata (Common limpet)

Barnacle

Chthamalus montagui

• Sell wall of 6 solid plates
• Kite-shaped opening of four plates
• Max diameter 14mm
• Found on all wave-exposed rocky shores

Dog whelk

Nucella lapillus

• Thick, conical shell with short pointed spire
• Aperture has a siphonal canal
• Max 3cm
• White, yellow, brown and striped
• Found on mid shore downwards
• Feeds on barnacles and mussels
• Shell thickness dependent upon wave exposure

Edible (common) periwinkle

Littorina littorea

• Largest British periwinkle
• Juveniles have conspicuous spiral ridges
• Max 5cm
• Generally black or dark grey-brown.
• Found on the upper shore to sublittoral zone

Painted topshell

Calliostoma zizyphinum

• Rounded apertures
• Iridescent colours

Pearly topshell

Margarites helicinus

• A translucent globe shell up to 9mm
• Light brown, orange or reddish
• Found from the lower shore to sublittoral zone

Purple topshell (or flat topshell)

Gibbula umbilicalis

• Cone-shaped shell with an eroded silvery top
• The aperture is large and round
• The small umbilicus is next to the aperture
• Greenish-grey with broad diagonal stripes of reddish purple
• Found from high water to lower shore