Exter Formation

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).^[1][2]

Exter Formation
Stratigraphic range: Rhaetian ~208–201 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Exter Formation at Krauthausen
Type	Formation
Unit of	Keuper
Sub-units	Rinteln, Oeynhausen & Vahlbruch Subformations
Underlies	Black Jurassic
Overlies	Arnstadt & Trossingen Formations
Thickness	Typically between 100 and 150 m (330 and 490 ft) Locally 250 m (820 ft) in northern Germany Up to 45 m (148 ft) in southern Germany
Lithology
Primary	Claystone, siltstone, sandstone
Other	Coal
Location
Coordinates	48.6°N 9.1°E / 48.6; 9.1
Approximate paleocoordinates	36.1°N 10.8°E / 36.1; 10.8
Region	Niedersachsen, Baden-Württemberg, Westphalia, Bavaria
Country	Germany
Extent	Widespread
Exter Formation (Germany)

Fossil content

The formation has provided fossils of:^[1][2]

Mammals

• Thomasia antiqua
• Haramiyidae indet.

Therapsids

• Chalepotherium plieningeri

Reptiles

• "Ichthyosaurus" rhaeticus
• Megalosaurus cloacinus
• Nothosaurus cloacinus
• Phytosaurus cubicodon?
• Phytosaurus cylindricodon?
• Plateosaurus ornatus
• Rhaeticosaurus mertensi^[3]
• Termatosaurus albertii
• Termatosaurus crocodilinus
• Plateosaurus sp.^[4]
• 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.

Insects

• Triassothemis gartzii^[5]

Flora

• Becklesia franconica^[6]

See also

• List of fossiliferous stratigraphic units in Germany