Limpets
Limpets are marine gastropod molluscs (Patella and related genera) with simple, compressed conical shells, clinging tenaciously to rocks in intertidal zones worldwide. Harvested by hand (levered off rocks) in many coastal regions — the Azores, Madeira, Hawaii (‘opihi), South Africa — and eaten raw or cooked (grilled, in stews), they have a chewy, briny flavour. They must come from clean, classified waters, since as grazing (not filter-feeding but surface-grazing) molluscs from the intertidal they can accumulate contaminants, heavy metals and algal biotoxins; proper handling, prompt chilling and thorough cooking keep them safe.