CRETACEOUS BRYOZOANS FROM THE CHATHAM ISLANDS, NEW-ZEALAND

Two bryozoan species have been found in the Kahuitara Tuff (Piripauan- Haumurian Stages; equivalent to Campanian-Maastrichtian) of Pitt Islan d, in the Chatham Islands, about 900 km east of the South Island of Ne w Zealand. Cretaceous bryozoans are rare in Australasia, and the two s pecies in this paper are the first to be formally described from New Z ealand. Both species have thick dendroid colonies but whereas Ceriocav a maculata sp. nov. is an unequivocal cerioporine cyclostome, the othe r species-Chiplonkarina campbelli sp. nov.-is more problematical and i s interpreted as an aberrant 'malacostegan' cheilostome. Like previous ly described species of Chiplonkarina, C. campbelli has interzooidal w alls with a central crenulated layer, indicating the former presence o f an intercalary cuticle of the type found in many cheilostomes but un known in cyclostomes. The anomalous global biogeographical distributio n of bryozoans during the Cretaceous is briefly discussed.