LAUSR

The so-called Oamaru Diatomite dates from approximately the Eocene–Oligocene Transition (∼34 million years ago), which is widely regarded as one of the most important climatic events of the entire Cenozoic era due to global cooling and the onset of continental-scale Antarctic glaciations. It also represents one of the richest fossil diatom deposits ever known and was first made famous owing to a series of diatom papers by Grove & Sturt. Based primarily on the collection of Sturt, supplemented by slides mounted by Grove, all curated in The Natural History Museum, we consider all 108 diatom taxa from the Oamaru Diatomite that were proposed in these seminal papers by Grove & Sturt and designate type specimens for 87 taxa that were not typified by previous workers, and for which nomenclatural types could be established. Light photomicrographs of all specimens interpreted as types are presented next to reproductions of the line drawings from Grove & Sturt publications to aid future workers on the Oamaru Diatomite, and on diatom evolution across this critical climatic phase of the Palaeogene period.