Early Archosauromorphs: The Crocodile and Dinosaur Precursors

EZCURRA, MARTÍN D.; JONES, A. S; GENTIL, ADRIEL R.; BUTLER, R. J.

Reference Module in Earth Systems and Environmental Sciences

Elsevier

Año: 2021 p. 175 - 185

2542-9000

Following the end-Permian mass extinction (c. 252 million years ago), archosaurian reptiles increased in abundance and diversity,coming to dominate Mesozoic terrestrial ecosystems from the Late Triassic onwards. Archosaurs (?ruling reptiles?) includedinosaurs and the flying pterosaurs, as well as modern birds, crocodilians, and a variety of Mesozoic groups that lie along thecrocodilian lineage (?crocodile-line archosaurs?). Archosaurs are diapsid reptiles that are part of a larger group known asArchosauromorpha and a less inclusive group known as Archosauriformes. Archosauriformes includes archosaurs and their closestrelatives, all of which share unique features of the skull such as an additional opening (the antorbital fenestra) between the eyesocket and the nostril. Archosauromorpha is a broader grouping that includes archosauriforms and all species more closely relatedto them than to lepidosaurs (e.g., tuataras, lizards, snakes).