Oooooops. That's actually an Argonauta argo (where A. tuberculata has come from I don't know).
The most interesting thing about this species in New Zealand is that no animals are known, although a few fine-condition shells like this have been found (I have many animals of A. nodosa, and many shells). Because the shell lacks buoyancy (like that of the unrelated Nautilus), it must occur here. It is, as the report says, an extremely rare beast/find.