Lesson plan
Archosaurus
Archosaurus (meaning "ruling lizard") is an extinct genus of carnivorous proterosuchid archosauriform reptile. Its fossils are dated to the latest Permian of Russia, it is one of the earliest known archosauriforms. The type and only species is Archosaurus rossicus, known from several fragmentary specimens which cumulatively represent parts of the skull and cervical vertebrae. It would have been long when fully grown. Archosaurus is the namesake of the Archosaurus zone (Vyazniki Assemblage), the final Late Permian tetrapod biozone in Russia. When first described in 1960, Archosaurus was considered the oldest known archosaur and a close relative of Proterosuchus from the Early Triassic. However, Archosauria in modern terms is considered a more restricted group which Archosaurus lies outside of. The "classic" definition of archosaur utilized prior to the widespread use of cladistics is now roughly equivalent to the clade Archosauriformes. Archosaurus is still considered the oldest undisputed archosauriform, as well as one of the few valid members of the family Proterosuchidae. A 2023 study placed Archosaurus in the new subfamily Chasmatosuchinae within the proterosuchids. This would make Archosaurus significantly derived despite being the oldest known archosauriform, indicating that significant diversification already occurred among proterosuchids during the Permian.
Article summary
Archosaurus (meaning "ruling lizard") is an extinct genus of carnivorous proterosuchid archosauriform reptile. Its fossils are dated to the latest Permian of Russia, it is one of the earliest known archosauriforms. The type and only species is Archosaurus rossicus, known from several fragmentary specimens which cumulatively represent parts of the skull and cervical vertebrae. It would have been long when fully grown. Archosaurus is the namesake of the Archosaurus zone (Vyazniki Assemblage), the final Late Permian tetrapod biozone in Russia. When first described in 1960, Archosaurus was considered the oldest known archosaur and a close relative of Proterosuchus from the Early Triassic. However, Archosauria in modern terms is considered a more restricted group which Archosaurus lies outside of. The "classic" definition of archosaur utilized prior to the widespread use of cladistics is now roughly equivalent to the clade Archosauriformes. Archosaurus is still considered the oldest undisputed archosauriform, as well as one of the few valid members of the family Proterosuchidae. A 2023 study placed Archosaurus in the new subfamily Chasmatosuchinae within the proterosuchids. This would make Archosaurus significantly derived despite being the oldest known archosauriform, indicating that significant diversification already occurred among proterosuchids during the Permian.
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Discussion questions
- Summarise the article in your own words. Which single claim would you verify first, and why?
- Which claim in this article is most likely to be revised as the sources update? How would you check its current status?
- If two sources disagreed about one of these facts, what would you need in order to trust one over the other?
Bibliography
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Key claims and bibliography are generated from the same tracked claims and sources as the article page.