Erfurt Formation

The Erfurt Formation, also known as the Lower Keuper (German: Untere Keuper, Lettenkeuper, Lettenkohle or Lettenkohlenkeuper), is a stratigraphic formation of the Keuper group and the Germanic Trias supergroup. It was deposited during the Ladinian stage of the Triassic period.^[2] It lies above the Upper Muschelkalk and below the Middle Keuper.^[1]

Erfurt Formation
Stratigraphic range: Ladinian ~242–237 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Outcrop of the formation at the Schumann quarry near Vellberg
Type	Geological formation
Unit of	Lower Keuper
Sub-units	Bairdienkalk, Grenzdolomit, Lettenkeuper, Sandige Pflanzenschiefer, Untere Graue Mergel & Werksandstein Members
Underlies	Grabfeld Formation
Overlies	Upper Muschelkalk
Thickness	20–700 m (66–2,297 ft)[1]
Lithology
Primary	Marl
Other	Claystone, dolomite, limestone, sandstone
Location
Coordinates	50.949036°N 11.070136°E / 50.949036; 11.070136
Approximate paleocoordinates	15.1°N 16.6°E / 15.1; 16.6
Region	Baden-Württemberg, Thuringia
Country	Germany
Extent	Mittelgebirge, North German Plain
Type section
Named for	Erfurt
Named by	Hoffmann
Year defined	1830
Erfurt Formation (Germany)

Lithostratigraphy of the Keuper of the Germanic basin

Definition

The formation was defined in Erfurt-Melchendorf in 1830 by Franz Xaver Hofmann and named for the nearby town of Erfurt.^[1]

The Erfurt Formation is underlain by the Upper Muschelkalk. The lower boundary to the Erfurt Formation is the "Lettenkohlensandstein" in northern Germany and the "Grenz-bone-beds" in southern Germany.

The formation is a sequence of dolomite, lacustrine limestones, claystone, evaporites, and fluviatile sandstones. The color is usually grey but can also be brown or reddish brown. The average thickness is 60 to 80 meter, with a maximum thickness of 700 meter in the Glückstadt-Graben.^[1]

The upper boundary is marked by dolomites, or claystones of the Grabfeld Formation.^[1]

Fossil content

Color key Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon		Notes Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

The Erfurt Formation is known for its vertebrate fossils. Different kinds of fish, amphibians and archosauriforms have been found. Usually they are found as bone beds, but in 1977 the first complete skeletons were found near Kupferzell. They include Mastodonsaurus, Gerrothorax, Plagiosuchus, Callistomordax, Nanogomphodon, Batrachotomus, Kupferzellia and Palaeoxyris friessi.^[3]

Reptiles

Reptiles reported from the Erfurt Formation
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Batrachotomus	B. kupferzellensis	Schwäbisch Hall.[4]	Albertischichten Member (Serrolepisbank).[4]		An archosaur.
Wirtembergia	W. hauboldae	Vellberg.[5]	Untere Graue Mergel.[5]	2 partial dentaries (SMNS 91060 & SMNS 91061),[5] and a partial skeleton (SMNS 91313).[6]	The oldest known rhynchocephalian.
Doswelliidae	Gen. et. sp. indet.	Schwäbisch Hall.[4]	Albertischichten Member (Serrolepisbank).[4]	An osteoderm (MHI 2078).[4]	An archosauriform.
Fraxinisaura	F. rozynekae	Vellberg, Baden-Württemberg.[7]	Untere Graue Mergel Layer.[7]		A basal lepidosauromorph.
Jaxtasuchus	J. salomoni	Baden-Württemberg.[8]	Estherienschichten to Anoplophora Dolomite.[8]	Multiple skeletal remains.[8]	A doswelliid.
Nothosaurus	N. cristatus	Eschenau Quarry, Baden-Württemberg.[9]	Lettenkeuper.[9]	Almost complete skull lacking mandible (GPIT/RE/09800).[9]	A nothosaur
	N. mirabilis	Hoheneck & Molsdorf.[10]	Upper Lettenkeuper.[10]	Multiple specimens.[10]	A nothosaur.
	N. sp.	Schwäbisch Hall.[4]	Albertischichten Member (Serrolepisbank).[4]	2 dorsal vertebrae & a thoracic rib.[4]	A nothosaur.
Owenettidae, aff. Barasaurus		Kupferzell locality & Schumann quarry.[11]		Left humerus (SMNS 92101) & right humerus (SMNS 92100).[11]	An owenettid.
Pappochelys	P. rosinae	Schumann Quarry, Eschenau, Vellberg.[12]	Top of Untere Graue Mergel.[12]	20 specimens.[12]	A stem-turtle.
Polymorphodon	P. adorfi	Schumann Quarry, Vellberg.[13]	Untere Graue Mergel.[13]	Disarticulated partial skeletons.[13]	An archosauriform.
Procolophonidae	Gen. indet. sp. indet.	Schumann Quarry.[11]		Left humerus (SMNS 91753).[11]	A procolophonid.
Psephosaurus	P. suevicus	Quarry "Hohenloher Steinwerk" & Hoheneck near Ludwigsburg.[14]		Isolated plates (MHI 1426/1-3 & SMNS 91007).[14]	A placodont.
	P. sp.	Hoheneck near Ludwigsburg.[14]		Isolated plates (SMNS 91008 & 91009).[14]	A placodont.
Rutiotomodon	R. tytthos	Schumann limestone quarry.[15]	Top of the Untere Graue Mergel.[15]	A nearly complete right maxilla with teeth (SMNS 97028) & a crushed dentary fragment (SMNS 97029).[15]	A trilophosaurid.
Simosaurus	S. gaillardoti	Hoheneck near Ludwigsburg.[16]	Lettenkeuper.[16]	Skull.[16]	A nothosaur.
	S. guilelmi	Hoheneck near Ludwigsburg.[16]	Lettenkeuper.[16]	Skull.[16]	Junior synonym of S. gaillardoti.
Smilodon	S. laevis	Gaildorf Alumn Mine.[17]		Jaw fragment with teeth.[17]	Preoccupied generic name, renamed Zanclodon laevis.
?Suchia	Indeterminate	Schwäbisch Hall.[4]	Albertischichten Member (Serrolepisbank).[4]	A tooth (MHI 2035).[4]	An archosaur.
Tanystropheus	T. conspicuus			Vertebrae.[18]	Nomen dubium.
	T. sp.	Steinbach near Crailsheim.[18]	Lower Lettenkeuper.[18]	Teeth & vertebrae.[18]	A tanystropheid.
Vellbergia	V. bartholomaei	Schumann Quarry, Vellberg.[19]	Untere Graue Mergel.[19]	Partial skull (SMNS 91590).[19]	A stem-lepidosauromorph.
Zanclodon	Z. laevis	Gaildorf Alumn Mine.[17]		Jaw fragment with teeth.[17]	An indeterminate archosaur.

Synapsids

Synapsids reported from the Erfurt Formation
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Aff. Dinodontosaurus		Neidenfels, Baden-Württemberg.[20]		Isolated complete left humerus (SMNS 56891).[20]	Specimen now thought to represent a temnospondyl.[20]
Nanogomphodon	N. wildi	Michelbach an der Bilz.[21]	Sandige Pflanzenschiefer Member, lower Lettenkeuper.[21]	Teeth.[21]	A cynodont.

Amphibians

Amphibians reported from the Erfurt Formation
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Bystrowiella	B. schumanni	Kupferzell & Vellberg, Hohenlohe.[22]	Untere Graue Mergel.[22]	Osteoderms & vertebrae.[22]	A chroniosuchian.
Callistomordax	C. kugleri	Vellberg (Schumann quarry), Ummenhofen quarry & Kupferzell locality.[23]	Albertibank through Untere Graue Mergel.[23]	Numerous specimens.[23]	A metoposauroid.
Gerrothorax	G. pulcherrimus	Schwäbisch Hall.[4]	Albertischichten Member (Serrolepisbank).[4]	Two skull fragments and some osteoderms.[4]	A plagiosaurid.
Mastodonsaurus	M. giganteus	Many localities in Baden-Württemberg, Bayern & in Thuringia.[4][24]	From the Grenzbonebed through the Hohenecker Kalk, covering nearly the whole Lettenkeuper sequence.[4][24]	Numerous specimens.[4][24]	A capitosaur.
Megalophthalma	M. ockerti	Schumann limestone quarry, Vellberg, Baden-Württemberg, southern Germany.[25]	Hauptsandstein (main sandstone unit).[25]	A partial skull with anterior portion of the left mandibular ramus (MHI 2047).[25]	A plagiosaurid.
Plagiosuchus	P. pustuliferus	Multiple localities in Baden-Württemberg & Thuringia.[26]	Vitriolschiefer, Sandige Pflanzenschiefer & Untere Graue Mergel.[26]	Multiple specimens.[26]	A plagiosaurid.
?Temnospondyli	Gen. et. sp. indet.	Neidenfels & Schumann Quarry.[20]	Untere Graue Mergel.[20]	Isolated complete left humerus (SMNS 56891) & isolated almost complete right humerus (SMNS 90571).[20]	Originally thought to represent a dicynodont similar to Dinodontosaurus.[20]
Trematolestes	T. hagdorni	Present in a range of localities in southern Germany.[27]	Estherienschichten through Untere Graue Mergel, upper Lettenkeuper.[27]	Numerous specimens including a nearly-complete skeleton.[27]	A trematosaurid.

Bony fish

Bony fish reported from the Erfurt Formation
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
"Ceratodus"	"C." concinnus	Schwäbisch Hall.[4]	Albertischichten Member (Serrolepisbank).[4]	Tooth plates, pterygoids & scales.[4]	A lungfish.
?Coelacanthidae	Gen. et. sp. indet.	Schwäbisch Hall.[4]	Albertischichten Member (Serrolepisbank).[4]	Numerous remains.[4]	A coelacanth.
Parundichna	P. schoelli	Rot am See, Baden-Württemberg.[28]	Hauptsandstein.[28]	Clusters of sigmoidal scratches (MHI 1704).[28]	Swimming trace of a large coelacanth.
Ptychoceratodus	P. serratus	Schwäbisch Hall.[4]	Albertischichten Member (Serrolepisbank).[4]	A mould of a juvenile left praearticular tooth (MHI 410) & a fragment of a juvenile tooth plate (MHI 1748/42).[4]	A lungfish.
?Redfieldiiformes	Fam., gen. et. sp. indet.	Schwäbisch Hall.[4]	Albertischichten Member (Serrolepisbank).[4]	2 fragmentary and dissociated skeletons.[4]	A redfieldiiform.
Saurichthys	S. gypsophilus	Franconia.[29]		Skull fragment.[29]	A saurichthyiform.
	S. sp.	Schwäbisch Hall.[4][29]	Albertischichten Member (Serreolepisbank).[4]	1 fragmentary rostrum (MHI 1748/27).[4][29]	A saurichthyiform.
Serrolepis	S. suevicus	Schwäbisch Hall.[4]	Albertischichten Member (Serrolepisbank).[4]	Numerous specimens.[4]	A perleidiform.

Cartilaginous fish

Cartilaginous fish reported from the Erfurt Formation
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Lonchidion	L. sp.	Schwäbisch Hall.[4]	Albertischichten Member (Serrolepisbank).[4]	Teeth.[4]	A hybodontiform.
Palaeoxyris	P. friessi	Muschelkalk quarry, Baden-Württemberg.[3]	Top of Hauptsandstein.[3]	SMNS 95447 (egg capsule).[3]	Likely an egg capsule of Polyacrodus.

References

1. "Erfurt Formation". BGR. Archived from the original on 10 February 2013. Retrieved 2 March 2013.
2. Erfurt Formation at Fossilworks.org
3. Ronald Böttcher (2010). "Description of the shark egg capsule Palaeoxyris friessi n. sp. from the Ladinian (Middle Triassic) of SW Germany and discussion of all known egg capsules from the Triassic of the Germanic Basin". Palaeodiversity. 3: 123–139. Retrieved 23 January 2012.
4. Hagdorn, Hans; Mutter, Raoul (January 2011). "The vertebrate fauna of the Lower Keuper Albertibank (Erfurt Formation, Middle Triassic) in the vicinity of Schwäbisch Hall (Baden-Württemberg, Germany)". Palaeodiversity. 4: 223–243.
5. Jones, Marc EH; Anderson, Cajsa Lisa; Hipsley, Christy A; Müller, Johannes; Evans, Susan E; Schoch, Rainer R (2013-09-25). "Integration of molecules and new fossils supports a Triassic origin for Lepidosauria (lizards, snakes, and tuatara)". BMC Evolutionary Biology. 13 (1): 208. Bibcode:2013BMCEE..13..208J. doi:10.1186/1471-2148-13-208. ISSN 1471-2148. PMC 4016551. PMID 24063680.
6. Sues, Hans-Dieter; Schoch, Rainer R. (2023-11-07). "The oldest known rhynchocephalian reptile from the Middle Triassic (Ladinian) of Germany and its phylogenetic position among Lepidosauromorpha". The Anatomical Record. 307 (4): 776–790. doi:10.1002/ar.25339. ISSN 1932-8486. PMID 37937325.
7. Rainer R. Schoch; Hans-Dieter Sues (18 April 2018). "A new lepidosauromorph reptile from the Middle Triassic (Ladinian) of Germany and its phylogenetic relationships". Journal of Vertebrate Paleontology. 38 (2): e1444619. Bibcode:2018JVPal..38E4619S. doi:10.1080/02724634.2018.1444619. S2CID 89753030.
8. Schoch, R. R.; Sues, H. D. (2013). "A new archosauriform reptile from the Middle Triassic (Ladinian) of Germany". Journal of Systematic Palaeontology. 12 (1): 113–131. doi:10.1080/14772019.2013.781066. S2CID 85401373.
9. Hinz, Juliane K.; Matzke, Andreas T.; Pfretzschner, Hans-Ulrich (2019-03-04). "A new nothosaur (Sauropterygia) from the Ladinian of Vellberg-Eschenau, southern Germany". Journal of Vertebrate Paleontology. 39 (2): e1585364. Bibcode:2019JVPal..39E5364H. doi:10.1080/02724634.2019.1585364. ISSN 0272-4634. S2CID 155775644.
10. Rieppel, O.; Wild, R. (1996). "A revision of the genus Nothosaurus (Reptilia: Sauropterygia) from the Germanic Triassic, with comments on the status of Conchiosaurus clavatus / Olivier Rieppel --, Rupert Wild --". doi:10.5962/bhl.title.2691. S2CID 89113375. {{cite journal}}: Cite journal requires |journal= (help)
11. Martinelli, Agustín G.; Soares, Marina Bento; Schoch, Rainer R. (January 2016). "Owenettids and procolophonids from the lower Keuper shed new light on the diversity of parareptiles in the German Middle Triassic". Journal of Paleontology. 90 (1): 92–101. Bibcode:2016JPal...90...92M. doi:10.1017/jpa.2016.26. ISSN 0022-3360. S2CID 132267938.
12. Schoch, Rainer R.; Sues, Hans-Dieter (24 June 2015). "A Middle Triassic stem-turtle and the evolution of the turtle body plan". Nature. 523 (7562): 584–587. Bibcode:2015Natur.523..584S. doi:10.1038/nature14472. ISSN 1476-4687. PMID 26106865. S2CID 205243837.
13. Sues, Hans-Dieter; Schoch, Rainer R.; Sobral, Gabriela; Irmis, Randall B. (2020). "A new archosauriform reptile with distinctive teeth from the Middle Triassic (Ladinian) of Germany". Journal of Vertebrate Paleontology. 40 (1): e1764968. Bibcode:2020JVPal..40E4968S. doi:10.1080/02724634.2020.1764968. hdl:10088/106576. ISSN 0272-4634. S2CID 221749201.
14. Scheyer, Torsten M. (December 2007). "Skeletal histology of the dermal armor of Placodontia: the occurrence of "postcranial fibro-cartilaginous bone" and its developmental implications". Journal of Anatomy. 211 (6): 737–753. doi:10.1111/j.1469-7580.2007.00815.x. PMC 2375852. PMID 17944862.
15. Sues, Hans-Dieter; Schoch, Rainer R. (March 2023). "A new Middle Triassic (Ladinian) trilophosaurid stem-archosaur from Germany increases diversity and temporal range of this clade". Royal Society Open Science. 10 (3): 230083. Bibcode:2023RSOS...1030083S. doi:10.1098/rsos.230083. ISSN 2054-5703. PMC 10031418. PMID 36968237.
16. Rieppel, Olivier (1994). Osteology of Simosaurus gaillardoti and the relationships of stem-group Sauropterygia. [Chicago, Ill.]: Field Museum of Natural History.
17. Schoch, Rainer R. (2011-04-01). "New archosauriform remains from the German Lower Keuper". Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen. 260 (1): 87–100. doi:10.1127/0077-7749/2011/0133. ISSN 0077-7749.
18. Spiekman, Stephan N. F.; Scheyer, Torsten M. (2019-12-16). "A taxonomic revision of the genus Tanystropheus (Archosauromorpha, Tanystropheidae)". Palaeontologia Electronica. 22 (3): 1–46. doi:10.26879/1038. ISSN 1094-8074. S2CID 211105850.
19. Sobral, Gabriela; Simões, Tiago R.; Schoch, Rainer R. (2020-02-20). "A tiny new Middle Triassic stem-lepidosauromorph from Germany: implications for the early evolution of lepidosauromorphs and the Vellberg fauna". Scientific Reports. 10 (1): 2273. Bibcode:2020NatSR..10.2273S. doi:10.1038/s41598-020-58883-x. ISSN 2045-2322. PMC 7033234. PMID 32080209. S2CID 211217331.
20. Maisch, Michael W. (2009-01-01). "No dicynodont in the Keuper - a reconsideration of the occurrence of aff. Dinodontosaurus in the Middle Triassic of Southern Germany". Palaeodiversity. 2: 271–278.
21. Hopson, James A.; Sues, Hans-Dieter (2006-06-01). "A traversodont cynodont from the Middle Triassic (Ladinian) of Baden-Württemberg (Germany)". Paläontologische Zeitschrift. 80 (2): 124–129. Bibcode:2006PalZ...80..124H. doi:10.1007/BF02988972. eISSN 1867-6812. ISSN 0031-0220. S2CID 128486943.
22. Witzmann, Florian; Schoch, Rainer R.; Maisch, Michael W. (2007). "A relict basal tetrapod from Germany: first evidence of a Triassic chroniosuchian outside Russia". Naturwissenschaften. 95 (1): 67–72. doi:10.1007/s00114-007-0291-6. ISSN 0028-1042. PMID 17653527. S2CID 8161364.
23. Schoch, R. R. (2008). "A new stereospondyl from the German Middle Triassic, and the origin of the Metoposauridae". Zoological Journal of the Linnean Society. 152: 79–113. doi:10.1111/j.1096-3642.2007.00363.x.
24. R., Schoch, Rainer (1999). Comparative osteology of Mastodonsaurus giganteus (Jaeger, 1828) from the Middle Triassic (Lettenkeuper: Longobardian) of Germany (Baden-Württemberg, Bayern, Thüringen). Staatl. Museum für Naturkunde. OCLC 247114091.{{cite book}}: CS1 maint: multiple names: authors list (link)
25. Schoch, Rainer R.; Milner, Andrew R.; Witzmann, Florian (September 2014). Ruta, Marcello (ed.). "Skull morphology and phylogenetic relationships of a new Middle Triassic plagiosaurid temnospondyl from Germany, and the evolution of plagiosaurid eyes". Palaeontology. 57 (5): 1045–1058. Bibcode:2014Palgy..57.1045S. doi:10.1111/pala.12101. S2CID 130014545.
26. Damiani, Ross; Schoch, Rainer R.; Hellrung, Hanna; Werneburg, Ralf; Gastou, STÉPHANIE (January 2009). "The plagiosaurid temnospondyl Plagiosuchus pustuliferus (Amphibia: Temnospondyli) from the Middle Triassic of Germany: anatomy and functional morphology of the skull". Zoological Journal of the Linnean Society. 155 (2): 348–373. doi:10.1111/j.1096-3642.2008.00444.x. ISSN 0024-4082.
27. Schoch, Rainer R. (2006). "A Complete Trematosaurid Amphibian from the Middle Triassic of Germany". Journal of Vertebrate Paleontology. 26 (1): 29–43. doi:10.1671/0272-4634(2006)26[29:ACTAFT]2.0.CO;2. ISSN 0272-4634. JSTOR 4524534. S2CID 85829091.
28. Simon, Theo; Hagdorn, Hans; Hagdorn, Magnus K.; Seilacher, Adolf (September 2003). "Swimming trace of a coelacanth fish from the Lower Keuper of south-west Germany". Palaeontology. 46 (5): 911–926. Bibcode:2003Palgy..46..911S. doi:10.1111/1475-4983.00326. ISSN 0031-0239. S2CID 140704105.
29. Romano, C.; Kogan, I.; Jenks, J.; Jerjen, I.; Brinkmann, W. (2012-09-28). "Saurichthys and other fossil fishes from the late Smithian (Early Triassic) of Bear Lake County (Idaho, USA), with a discussion of saurichthyid palaeogeography and evolution". Bulletin of Geosciences: 543–570. doi:10.3140/bull.geosci.1337. ISSN 1802-8225.