Serpukhovian


The Serpukhovian is in the ICS geologic timescale the uppermost stage or youngest age of the Mississippian, the lower subsystem of the Carboniferous. The Serpukhovian age lasted from Ma to Ma. It is preceded by the Visean and is followed by the Bashkirian.
The Serpukhovian correlates with the lower part of the Namurian stage of European stratigraphy and the middle and upper parts of the Chesterian stage of North American stratigraphy.

Name and definition

The Serpukhovian stage was proposed in 1890 by Russian stratigrapher Sergei Nikitin and was introduced in the official stratigraphy of European Russia in 1974. It was named after the city of Serpukhov, near Moscow. The ICS later used the upper Russian subdivisions of the Carboniferous in its international geologic time scale.
The base of the Serpukhovian is at the first appearance of the conodont Lochriea crusiformis. In 2007, no GSSP had been assigned to the Serpukhovian stage yet. The top of the stage is at the first appearance of the conodont Declinognathodus nodiliferus. It is also slightly above the first appearance of the foram Globivalvulina bulloides, genozone of the ammonoid genus Homoceras and the ammonoid biozone of Isohomoceras subglobosum.

Subdivision

The Serpukhovian stage includes four conodont biozones:
In Russian stratigraphy, the Serpukhovian is subdivided into three substages, from bottom to top: Tarusian, Steshevian, and Protvian, named after places near Serpukhov. In British stratigraphy, the Serpukhovian contains three substages. These are from bottom to top: Pendleian, Arnsbergian and Chokierian.

Serpukhovian life

Cartilaginous fishes

Coelacanths

Tetrapodomorphs

Reptiliomorphs

Literature