| Westbury Formation | |
| Type: | Geological formation |
| Period: | Rhaetian |
| Prilithology: | Mudstone, Shale |
| Otherlithology: | Limestone, Sandstone |
| Namedfor: | Westbury-on-Severn |
| Region: | Europe |
| Unitof: | Penarth Group |
| Underlies: | Lilstock Formation |
| Overlies: | Blue Anchor Formation |
| Thickness: | 5-10 m |
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]
| Vertebrates reported from the Westbury Formation | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
| Avalonianus[4] | A. sanfordi | Wedmore Hill | "Several now lost teeth." | |||
| Camelotia | C. borealis | Westbury-on-Severn[5] | "Vertebrae, pubis, ischium, femur, tibia, phalanges, adult."[6] | |||
| Ichthyotitan[7] | I. severnensis | Blue Anchor and Lilstock | Two partial surangulars | Possibly one of the largest marine reptiles | ||
| Picrodon | P. herveyi | Wedmore Hill | "Tooth." | |||
| Shastasauridae | Indeterminate | Aust | "Three partial specimens." | |||
| Pachystropheus[8] | Several partial postcranial skeletons | A small thalattosaurian marine reptile, youngest known thalattosaur | ||||
| Lissodus | L. minimus | A hybodont shark | ||||
| Saurichthys | A pike or gar-like predatory fish | |||||
| Sargodon | A dapediiform fish | |||||
| Gyrolepis | A ray-finned fish | |||||
| Birgeria | A large predatory fish | |||||
| Ceratodus | A lungfish | |||||