Protosuchia

fossil reptile suborder

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Last updated

July 13, 2026

Quick Summary

The Protosuchia were an early group of reptiles that lived during the Late Triassic Epoch, approximately 237 to 201.4 million years ago. They are considered the most primitive representatives of the crocodilian group.1

Key characteristics of Protosuchia include:
* They belonged to the subclass Archosauria, sharing traits with dinosaurs, crocodiles, and birds.12
* Like other reptiles, they were diapsids, possessing two openings on each side of their skull.12
* Their teeth grew from sockets, and their skulls lacked an opening for the parietal organ.1
* A defining feature was the development of a secondary bony palate, which enclosed the nasal passage.1
* Compared to later crocodiles, Protosuchia had very short muzzles, and their internal nostrils (choanae) were located further forward on the palate.1

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crocodile
Annotated classification
†Suborder Protosuchia Upper Triassic; muzzle very short; choanae (internal nostrils) in region of palatine bones. †Suborder Mesosuchia Jurassic to Upper Cretaceous; choanae in posterior part of palatine bones. †Suborder Sebecosuchia Upper Cretaceous to Miocene;
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†Suborder Protosuchia Upper Triassic; muzzle very short; choanae (internal nostrils) in region of palatine bones. †Suborder Mesosuchia Jurassic to Upper Cretaceous; choanae in posterior part of palatine bones. †Suborder Sebecosuchia Upper Cretaceous to Miocene;
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crocodile
Paleontology
…the crocodilian group, namely the Protosuchia of the Late Triassic Epoch (237 million–201.4 million years ago); but their muzzles were very short, and the choanae were relatively far forward on the palate.
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…the crocodilian group, namely the Protosuchia of the Late Triassic Epoch (237 million–201.4 million years ago); but their muzzles were very short, and the choanae were relatively far forward on the palate.
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