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A new cheilostome bryozoan genus, Powellitheca gen. nov., is erected here for three species from New Zealand, one of which has been previously assigned to Emballotheca Levinsen, 1909, but which differ significantly from the Australian type species of Emballotheca, E. quadrata (MacGillivray, 1880). Notably, whereas Emballotheca has a cormidial orifice (i.e., formed by numerous neighbouring zooids), and lepralielliform ooecia, the orifice of Powellitheca gen. nov. is formed by single zooids and ooecia are of the microporelliform type. The introduction of a new family, Powellithecidae fam. nov., becomes necessary because of the nonconformity of Powellitheca gen. nov. with other known families having microporelliform ooecia. In addition to the Recent type species Powellitheca terranovae gen. et sp. nov., one other new Recent species, P. labiosa gen. et sp. nov., and a Plio-Pleistocene fossil species, Monoporella waipukurensis Waters, 1887, are assigned to the new genus.
Three new fossil bryozoan species, a ctenostome and two cheilostomes, are described and figured from Pleistocene strata of the Wanganui Basin, New Zealand. Buskia waiinuensis sp. nov., a soft-body ctenostome preserved as a mould bioimmuration, is the first fossil record of the genus from New Zealand. Microporella rusti sp. nov., which is notable for the lack of ooecia in the large suite of colonies available, is one of the most common bryozoans in the Nukumaru Limestone and Nukumaru Brown Sand shellbeds, forming large encrusting sheet-like colonies, but is uncommon in younger beds. Rare, small-sized colonies of Parkermavella columnaris sp. nov. were found as fossil in two Quaternary beds, the Nukumaru Limestone and the Upper Kai-Iwi Shellbed, and also alive on rocks from greater Cook Strait area.