Abstract
The radiolarians from the Campanian–Maastrichtian deposits of the Vaamychgyn unit sequence (Yakenmyveem River, Koryak Upland, Ekonai terrane) were studied for the first time. On the basis of the joint occurrence of Excentrosphaerella vivenkensis (Lipman), Lithomespilus mendosa (Krasheninnikov), and Stichomitra livermorensis Campbell et Clark, the studied complex is attributed to the Campanian–Maastrichtian. The assemblage contains abundant representatives of the family Heliodiscidae Haeckel, which are widely common in the Boreal and Austral realms and can be of high importance for the stratigraphic and paleobiogeographic paleoreconstructions. The new data allow one to establish the time of the first occurrence of Excentrosphaerella teuria (Hollis), which was previously known only from the Early Paleocene. The species Cromyosphaera vivenkensis Lipman is attributed in this work to the genus Excentrosphaerella Dumitrica.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
