Palaeogene triserial planktonic foraminifera

Abstract. Triserial planktonic foraminiferal species from the Palaeogene are classified into the Early Danian Guembelitria, with pore mounds on the test surface, and the Early Eocene-Late Oligocene Jenkinsina, which are also microperforate but lack pore mounds. The stratigraphic and palaeogeographic ranges are discussed, the holotype of G. cretacea Cushman (the type species of Guembelitria) is re-illustrated, and neotypes designated for G. danica (Hofker) and Jenkinsina triseriata (Terquem). Chiloguembelitria is shown to be a junior synonym of Guembelitria.