The Exter Formation is the only formation of the Upper Keuper or Rhätsandstein, and is a geologic formation in Germany. It preserves fossils dating back to the Rhaetian of the Triassic period (specifically around 205 Ma).
Fossil content
The formation has provided fossils of:
Mammals
Thomasia antiqua
Haramiyidae indet.
Therapsids
Chalepotherium plieningeri
Reptiles
"Ichthyosaurus" rhaeticus
Megalosaurus cloacinus
Nothosaurus cloacinus
Phytosaurus cubicodon? Phytosaurus cylindricodon? Plateosaurus ornatus Rhaeticosaurus mertensi Termatosaurus albertii Termatosaurus crocodilinus Plateosaurus sp. Plesiosauria indet.
Fish
Ceratodus cloacinus
C. heteromorphus
C. parvus
C. trapezoides
Hybodus cloacinus
H. sublaevis
Lissodus minimus
Nemacanthus monilifer
Sargodon tomicus
Acrodus sp. Asterolepis sp. Raja sp.
