Cockle Shells

Until recently I didn't realise that there were several different species of cockle around Britains shores. I think that I have the shells of two different species here - on the right the common cockle (Cerastoderma edule) and on the left the prickly cockle (Acanthocardia echinata). Identification from the shell can be difficult because the shell may be worn thin from time and tide.

On the inside the ribs of the prickly cockle are visible over the whole shell whereas those of the common cockle are only visible towards the outer margin.

In the prickly cockle the outer surface is covered in raised spines though these become worn in beached shells. To confuse matters further there is also a spiny cockle ((Acanthocardia aculeata) and identification between the two can be difficult.