The New ZealandBluff Oyster, Tiostrea lutaria, is a species of bivalve mollusc that is present around much of New Zealand. Ranging from the Bay of Islands to Stewart Island.
They are prized as a delicacy and are harvested during the month of March from the Foveaux Strait oyster fishery.
There is also a self-sustaining population in the Menai Strait which were accidentally introduced from the Fisheries Laboratory, Conwy, in 1965 or 1966 (sources disagree).
Tiostrea lutaria is though to be conspecific with the Chilean Oyster, Tiostrea chilensis.