A NEW CHEILOSTOME BRYOZOAN FROM THE CRETACEOUS OF INDIA AND EUROPE - A CYCLOSTOME HOMEOMORPH

The new 'malacostegan' cheilostome Chiplonkarina is an unusual genus p reviously misidentified as a cerioporine cyclostome because of extreme homeomorphy in both zooid-level and colony-level morphology. The type species, C. dimorphopora, is the dominant bryozoan in west-central In dia in the mid-Cretaceous Bagh Group, whose geology is briefly reviewe d, and is recorded here for the first time in the Cenomanian of France . A second species, C. bretoni sp. nov., occurs in the Lower Cenomania n of France and Germany. In common with many free-walled cyclostomes ( and other stenolaemates), the zooids of Chiplonkarina are long and tub ular, and branches of the dendroid colonies have axial endozones with zooids orientated parallel to the direction of branch extension, bendi ng through almost 90 degrees into the surrounding exozone, where zooid s are oriented perpendicular to the branch surface such that their len gthening caused branches to thicken. However, the presence of a cuticu lar layer in the interzooidal walls, fibrous wall microstructure, and the morphology of the colony base and overgrowths demonstrate that Chi plonkarina is a cheilostome. Chiplonkarina can be viewed as an early c heilostome 'experiment' in erect growth using a typically stenolaemato us growth pattern seldom repeated by the numerous erect cheilostomes t hat evolved subsequently. The presence of Chiplonkarina in the Nilkant h Formation ('Upper Tal Shell Limestone') of Uttar Pradesh, India supp orts the correlation of these deposits with the Bagh Group and implies a likely Cenomanian-Turonian age.