Famennian

The Famennian is the latter of two faunal stages in the Late Devonian epoch. It lasted from 372.2 million years ago to 358.9 million years ago. It was preceded by the Frasnian stage and followed by the Tournaisian stage.

It was during this age that tetrapods first appeared. In the seas, a novel major group of ammonoid cephalopods called clymeniids appeared, underwent tremendous diversification and spread worldwide, then just as suddenly went extinct.

The beginning of the Famennian is marked by a major extinction event, the Kellwasser Event, and the end with a smaller but still quite severe extinction event, the Hangenberg Event.

North American subdivisions of the Famennian include the Chautauquan, Canadaway, Conneaut, Conneautan, Conewango and Conewangan.

The Famennian stage was proposed in 1855 by Belgian geologist André Hubert Dumont and was accepted for the upper stage of the Upper Devonian by the Subcommission on Devonian Stratigraphy in 1981. It is named after Famenne, a natural region in southern Belgium.

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