Ok. I've read the story and it's mostly ignorant rubbish. The picture looks like
Argonauta argo, though it could be
A. nodosa. Both species are known from NZ waters.
As for the whole 'giant tuatua' part, it's bollocks. He most likely found an example of another related (and larger) species. The tuatua (
Paphies subtriangulata) is an abundant bivalve from exposed sandy beaches and gets to about 80mm (3 inches) in length. What this ignoramous probably found was a Toheroa (
Paphies ventricosa which is morphologically very similar, but bigger, ~120-160mm (~6 inch) bivalve. It could also have been
Paphies donacina, but that's not really that important.
What pisses me off here is lay-people pretending to be experts when they essentially know squat...
"It was possible that global warming was making our shellfish bigger, he said."
It's also possible that you are a cheese burger...
