A new species of Late Cretaceous wood-boring bivalve from New Zealand

A new species of late Campanian or Maastrichtian (Late Cretaceous) pholadid bivalve, Pholadidea (Hatasia) wiffenae, is described from shallow marine transgressive Maungataniwha Sandstone, northwestern Hawkes Bay, New Zealand. It represents the earliest confirmed record for both genus and subgenus. The new species is known from exceptionally well-preserved material, which permits detailed knowledge of external morphology, including all accessory plates, and to a lesser degree, internal morphology. It is assigned to Pholadidea (Hatasia) based largely on the nature of accessory plates. In life-habit and some details of morphology, however. P. (H.) wiffenae resembles Opertochasma and Martesia, and may be an evolutionary intermediate between Cretaceous Opertochasma and early Tertiary Pholadidea and Martesia. The present record highlights the need for a comprehensive systematic review of Mesozoic pholadids.