The Klettgau Formation is a geological formation in Switzerland. It is Late Triassic in age, covering most of the mid to late Norian, the Carnian, and into the Rhaetian, spanning a period of 26-30 million years.^[1]

The primary depositional environment was that of a playa with marine and fluvial intercalations. The lithology is quite variable consisting primarily of fine grained rocks typically claystones and dolocretes, often with sandstone or carbonatic fluvial channel fills.^[2]

Dinosaur fossils are known from the formation, including those of Plateosaurus, Notatesseraeraptor frickensis and Schleitheimia^[3][4]

The following other fossils were found in the formation:^[1]

Prozostrodontia

• Hallautherium schalchi^[5]
• Helvetiodon schutzi^[5]
• ?Thomasia sp.^[6]
• cf. Thomasia sp.^[6]
• Thomasia antiqua^[6]
• T. moorei^[6]
• Tricuspes cf. tuebingensis^[6]
• ?Haramiyidae indet.^[6]
• Morganucodon peyeri
• Morganucodon sp.

Reptiles

• Deltadectes elvetica^[7]
• Termatosaurus albertii^[6]
• Proganochelys quenstedtii^[8]
• Paleollanosaurus sp.^[7]
• ?Variodens sp.^[6]
• cf. Diphydontosaurus sp.^[7]
• cf. Eudimorphodon sp.^[6]
• Archosauriformes indet.^[9]
• Nothosauridae indet.^[6]
• Pterosauria indet.^[6]
• Sphenodontia indet.^[7]
• Theropoda indet.^[10]

Amphibians

• Labyrinthodontia indet.^[6]

Fish

Invertebrates

• Carrano, M. T (2020), Taxonomic opinions on the Dinosauria, unpublished
• Rauhut, Oliver W. M.; Holwerda, Femke M.; Furrer, Heinz (2020), "A derived sauropodiform dinosaur and other sauropodomorph material from the Late Triassic of Canton Schaffhausen, Switzerland", Swiss Journal of Geosciences, 113 (1): 8, doi:10.1186/s00015-020-00360-8, ISSN 1661-8726
• Zahner, M.; Brinkmann, W. (2019), "A Triassic averostran-line theropod from Switzerland and the early evolution of dinosaurs", Nature Ecology & Evolution, 3 (8): 1146–1152, Bibcode:2019NatEE...3.1146Z, doi:10.1038/s41559-019-0941-z, ISSN 2397-334X, PMC 6669044, PMID 31285577
• Whiteside, D. I.; Duffin, C. J.; Furrer, H. (2017), "The Late Triassic lepidosaur fauna from Hallau, North-Eastern Switzerland, and a new 'basal' rhynchocephalian Deltadectes elvetica gen. et sp. nov.", Neues Jahrbuch für Geologie und Paläontologie, 285: 53–74, doi:10.1127/njgpa/2017/0669
• Jordan, Peter; Pietsch, Johannes S.; Bläsi, Hansruedi; Furrer, Heinz; Kündig, Nicole; Looser, Nathan; Wetzel, Andreas; Deplazes, Gaudenz (2016), "The middle to late Triassic Bänkerjoch and Klettgau formations of northern Switzerland", Swiss Journal of Geosciences, 109 (2): 257–284, doi:10.1007/s00015-016-0218-3, ISSN 1661-8726
• Butler, R. J.; Porro, L. B.; Heckert, A. B. (2006), "A supposed heterodontosaurid tooth from the Rhaetian of Switzerland and a reassessment of the European Late Triassic record of Ornithischia (Dinosauria)", Neues Jahrbuch für Geologie und Paläontologie - Monatshefte, 2006 (10): 613–633, doi:10.1127/njgpm/2006/2006/613
• Tatarinov, L. P (1985), "New data on a collection of tetrapod teeth from the Rhaetian of Hallau (Switzerland)", Paleontological Journal, 1: 138–140
• Clemens, W. A (1980), "Rhaeto-Liassic mammals from Switzerland and West Germany", Zitteliana, 5: 51–92
• Peyer, B (1956), "Über Zähne von Haramiyiden, von Triconodonten und von wahrscheinlich synapsiden Reptilien aus dem Rhät von Hallau, Kt. Schaffhausen, Schweiz - On the teeth of haramiyids, triconodonts, and probable synapsid reptiles from the Rhaetic of Hallau, Kanton Schaffhausen, Switzerland", Schweizerische Paläontologische Abhandlungen, 72: 1–72
• Schalch, F.; Peyer, B. (1919), "Über ein neues Rhätvorkommen im Keuper des Donau-Rheinzuges - On a new occurrence of the Rhaetian in the Keuper of the Danube-Rhine valleys", Mitteilungen der Badischen Geologischen Landesanstalt, 8: 263–315