Them? They’re called bayla, love. The Aussies buy ‘em for the shell and throw the meat away. The Chinese people bash through the shell to get to the meat.
We were talking about the one in the front at the bottom. I can’t find out anything much about them, other than that it seems to be a gastropod(!) May even have the name wrong – although I made him spell it out for me I didn’t write it down. Anyone ever eaten one?