Hammer Head With attached Spiny Oyster Shells Rare 6-7"

These are Spiny oysters growing on a hammer head oyster,very unique. Large 6-7" specimen, No two animals are the same they all very which means these are a one of a kind collectors item...

Very interesting creatures which attach themselves to hard surfaces where they remain, unlike other molluscs. Shell is hinged together with a ball and socket joint rather than with a toothed hinge as with other clams. When threatened, it closes its shell tightly using powerful abductor muscles to exhibit menacing spines to predators. Interesting sex life in that many change from male to female during lifetime.