The Selandian is a stage in the Paleocene. It spans the time between 61.6 and 59.2 Ma. It is preceded by the Danian and followed by the Thanetian. Sometimes the Paleocene is subdivided in subepochs, in which the Selandian forms the "middle Paleocene".

The Paleocene, or Palaeocene, is a geological epoch that lasted from about 66 to 56 million years ago (mya). It is the first epoch of the Paleogene Period in the modern Cenozoic Era. The name is a combination of the Ancient Greek παλαιός palaiós meaning "old" and the Eocene Epoch, translating to "the old part of the Eocene".