Abstract

GUERSTEIN, G. Raquel; JUNCIEL, Gabriela L.; GULER, M.Verónica  and  DANERS, Gloria. Diconodinium lurense sp. nov., a late Maastrichtian to Danian dinoflagellate cyst from southwest Atlantic basins. Ameghiniana [online]. 2005, vol.42, n.2, pp.329-338. ISSN 1851-8044.

Upper Cretaceous and Cenozoic deposits from the Colorado and Austral basins, Argentina and the Punta del Este Basin, Uruguay contain diverse organic-walled dinoflagellate cysts, including Diconodinium lurense sp. nov. which occurs in the late Maastrichtian and Danian throughout the basins. The new species is characterized by an autophragm that is densely covered by short spines and by relatively long apical and antapical horns, and by a variable Ia to IPa archeopyle. On our evidence, the stratigraphical range of Diconodinium lurense sp. nov. is latest Maastrichtian to Danian, and is thus a useful biostratigraphical marker for the Cretaceous-Palaeogene transition in the southwest Atlantic basins.

Keywords : Biostratigraphy; Dinoflagellate cysts; Late Maastrichtian-Danian; Southwest Atlantic.