Westbury Formation

Westbury Formation
Stratigraphic range: Rhaetian PreꞒ Ꞓ O S D C P T J K Pg N
Type	Geological formation
Unit of	Penarth Group
Underlies	Lilstock Formation
Overlies	Blue Anchor Formation
Thickness	5-10 m
Lithology
Primary	Mudstone, Shale
Other	Limestone, Sandstone
Location
Region	Europe
Country	UK
Type section
Named for	Westbury-on-Severn

The Westbury Formation is a geological formation in England, one of the Penarth Group. It dates back to the Rhaetian.^[1] The formation is named after the village of Westbury-on-Severn in Gloucestershire.^[2] The remains of a giant shastasaurid and dinosaurs are known from the formation.^[3][4]

Vertebrate fauna

Vertebrates reported from the Westbury Formation
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Avalonianus[5]	A. sanfordi[5]	Wedmore Hill[5]		"Several now lost teeth."[5]
Camelotia[1]	C. borealis[1]	Westbury-on-Severn[6]		"Vertebrae, pubis, ischium, femur, tibia, phalanges, adult."[7]		Camelotia
Ichthyotitan[4]	I. severnensis[4]	Blue Anchor and Lilstock[4]		Two partial surangulars[3]	Possibly one of the largest marine reptiles
Picrodon[5]	P. herveyi[5]	Wedmore Hill[5]		"Tooth."[5]
Shastasauridae[3]	Indeterminate[3]	Aust[3]		"Three partial specimens."[3]
Pachystropheus[8]				Several partial postcranial skeletons	A small thalattosaurian marine reptile, youngest known thalattosaur
Lissodus[8]	L. minimus				A hybodont shark
Saurichthys[8]					A pike or gar-like predatory fish
Sargodon[8]					A dapediiform fish
Gyrolepis[8]					A ray-finned fish
Birgeria[8]					A large predatory fish
Ceratodus[8]					A lungfish

See also

• List of dinosaur-bearing rock formations

References

1. Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Triassic, Europe)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 521–525. ISBN 0-520-24209-2.
2. The BGS Lexicon of Named Rock Units — Result Details: Westbury Formation
3. Lomax, Dean R.; De la Salle, Paul; Massare, Judy A.; Gallois, Ramues (2018-04-09). Wong, William Oki (ed.). "A giant Late Triassic ichthyosaur from the UK and a reinterpretation of the Aust Cliff 'dinosaurian' bones". PLOS ONE. 13 (4): e0194742. Bibcode:2018PLoSO..1394742L. doi:10.1371/journal.pone.0194742. ISSN 1932-6203. PMC 5890986. PMID 29630618.
4. Lomax, D. R.; de la Salle, P.; Perillo, M.; Reynolds, J.; Reynolds, R.; Waldron, J. F. (2024). "The last giants: New evidence for giant Late Triassic (Rhaetian) ichthyosaurs from the UK". PLOS ONE. 19 (4). e0300289. doi:10.1371/journal.pone.0300289. PMC 11023487.
5. H. G. Seeley. (1898). On large terrestrial saurians from the Rhaetic Beds of Wedmore Hill, described as Avalonia sanfordi and Picrodon herveyi. Geological Magazine, decade 4 5:1-6
6. Galton, P. M. (1985). Notes on the Melanorosauridae, a family of large prosauropod dinosaurs (Saurischia: Sauropodomorpha). Geobios, 18(5), 671-676.
7. "Table 12.1," in Weishampel, et al. (2004). Page 234.
8. Quinn, Jacob G.; Matheau-Raven, Evangelos R.; Whiteside, David I.; Marshall, John E. A.; Hutchinson, Deborah J.; Benton, Michael J. (2024-06-04). "The relationships and paleoecology of Pachystropheus rhaeticus , an enigmatic latest Triassic marine reptile (Diapsida: Thalattosauria)". Journal of Vertebrate Paleontology. doi:10.1080/02724634.2024.2350408. ISSN 0272-4634.