Article: Upper Cretaceous ostracods from California

A limited exposure of Upper Cretaceous marine siltstones and claystones near the coastal town of Carlsbad, California, contains a remarkably well-preserved microfauna.Twenty-six species of ostracods including twenty-three new species and one new trachyleberid genus occur in the upper part of the section. This faunule possesses distinct Cenozoic affinities expressed by the presence of the genera Trachyleberis, Actinocythereis, and Idiocythere, all of which have previously been reported from rocks not older than Lower Tertiary. Generic affinities with European forms are also indicated by new species of Idiocythere, previously recorded only from the Eocene of Germany and Isocythereis, previously known only from the Cretaceous of Germany. Three species which also occur in Upper Cretaceous rocks of the U.S. Gulf Coast are present: Brachycythere darensis Swain 1952, Krithe cushmani Alexander 1929, and Cytheropteron coryelli Schmidt 1948.