The Ypresian is the first stage of the
EoceneEpoch and usually corresponds to the Early Eocene subepoch, though sometimes the Lutetianis included therein.
It spans the time between 55.8 ± 0.2 Ma and 48.6 ± 0.2 Ma (million years ago). The stage is named after
Ypres, Belgium. The famous Messel shalesin Germanyare from this age. Primates had appeared by 55 MaFact|date=August 2008, although the molecular clockand new paleontological finds state that they may have existed as early as the Late Cretaceous, 90 Ma.
Paleocene-Eocene Thermal Maximum
* [http://www.stratigraphy.org/geowhen/stages/Ypresian.html GeoWhen Database - Ypresian]
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