 Dosinia anus

Dosinia anus, commonly named the ringed dosinia, coarse dosinia, coarse biscuit shell and tuangi-haruru, in the Māori language, is a species of saltwater clam, a marine bivalve mollusc in the family Veneridae, the venus clams.The species is common to both of the main islands of New Zealand, where it is the largest and heaviest species in the genus, occasionally exceeding 80 mm in diameter.