The System of the Rotaliidae, an Overview

Abstract

Large Paleogene Rotaliidae all represent moderate K-strategists similar to the nummulitids to which they are associated. They arise as Tethys-wide groups during the Paleocene and reach their highest diversity during the earliest Lower Eocene (SBZ 5). They document a Global Community Maturation cycle that ends for the rotaliids by their disappearance after the Middle Eocene while other groups like the nummulitids and the orthophragminiforms continue up to the Eocene-Oligocene boundary. Under the generic definitions the species are grouped in order to reflect what is supposed to represent a phylogenetic lineage in the order of their appearance in geological time. This meets the demands of an easier taxonomic identification and to reflect in the same time a phylogenetic hypothesis.