Dinoflagellate cysts from the Upper Cretaceous (Campanian-Maastrichtian) from The Naze Peninsula, James Ross Island, Antarctica

We present the results of the quantitative and qualitative study of dinoflagellate cysts in outcrop samples from a section of the Snow Hill Island Formation (SHF) in James Ross Island, Antarctic. Dinoflagellate cysts assemblages are abundant and dominated by gonyaulacoid taxa. The last occurrence of the dino-flagellate cyst Kallosphaeridium? helbyi and Chatangiella granulifera, together with the first occurrence of Pterodinium cretaceum, indicates a probable late Campanian age (-76.4--72.1 Ma) for the lower strata. Whereas the first occurrence of Manumiella bertodano and the last occurrence of Odontochitina oper-culata, Xenascus ceratioides, and Stiphrosphaeridium anthophorum indicate an early Maastrichtian (-72.1--70.0 Ma) age for the upper strata. Our results, combined with paleobotanical and palynological published data, indicate medium-high continental and marine productivity with temperate paleo-climate free of glaciers for this interval. Lithological and paleontological data indicate mainly inner neritic marine depositional environments. The predominance of shales in the lower part of the lower Maas-trichtian interval indicates a slightly deeper environment. In contrast, in the middle part of the lower Maastrichtian, a shallower, transitional environment is marked by the presence of theropod dinosaurs and decapod crustaceans.& COPY; 2022 Elsevier Ltd. All rights reserved.