Sea Potato (Echinocardium cordatum), profile view of rare burrowing sea urchin showing detail of hairs on shell, on sandy seabed, St Abbs, Scotland, UK

underwater sea potato potatoes potato echinocardium cordatum sea urchin urchin rare burrowing sea urchins hairs shells one animal shell sandy seabed sea bottom st abbs scotland uk united kingdom sand sealife sea life