A spikey cockle at Weymouth

I found this spikey-shelled cockle on the beach at Weymouth. The tide was out and had left a series of shallow sandy ripples. Bait diggers had created some deep holes and I think that was how the cockle came to be lying on the surface in a ripple valley. It was sucking in water and periodically squirting it out.

I am not sure of its identity. It looks a lot like the Spiny Cockles (Acanthocardia aculeata) I find on Gower beaches but its overall appearance, size, and the sharpness of the spines make me think it is either a Prickly (Acanthocardia echinata) or a Rough Cockle (Acanthocardia tuberculata). Because it was alive and I returned it to the sediments, I could not examine the teeth in the hinge area or the inside of the shell, which would have provided vital clues. I’ll have to look out for empty Acanthocardia shells on the beach when I next visit Weymouth.

Click here for more pictures and information about Spiny Cockles in Jessica’s Nature Blog.