The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS).
[9] The base of the Campanian Stage is defined as a place in the stratigraphic column where the extinction of crinoid species Marsupites testudinarius is located.
[2] The top of the Campanian stage is defined as the place in the stratigraphic column where the ammonite Pachydiscus neubergicus first appears.
In North America, for example, the number of known dinosaur genera rises from four at the base of the Campanian to forty-eight in the upper part.
The generally warm climates and large continental area covered in shallow sea during the Campanian probably favoured the dinosaurs.