| Azendohsaurus | |
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| An Azendohsaurus tooth, the paratype specimen (MNHN-ALM 424) of A. laaroussii | |
Scientific classification 
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| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Clade: | Archosauromorpha |
| Clade: | Crocopoda |
| Clade: | †Allokotosauria |
| Family: | †Azendohsauridae |
| Genus: | †Azendohsaurus Dutuit, 1972 |
| Type species | |
| †Azendohsaurus laaroussii Dutuit, 1972
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| Species | |
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Azendohsaurus is an extinct genus of herbivorous archosauromorph reptile from roughly the late Middle to early Late Triassic Period of Morocco and Madagascar. The type species, Azendohsaurus laaroussii, was described and named by Jean-Michel Dutuit in 1972 based on partial jaw fragments and some teeth from Morocco. A second species from Madagascar, A. madagaskarensis, was first described in 2010 by John J. Flynn and colleagues from a multitude of specimens representing almost the entire skeleton. The generic name "Azendoh lizard" is for the village of Azendoh, a local village near where it was first discovered in the Atlas Mountains. It was a bulky quadruped that unlike other early archosauromorphs had a relatively short tail and robust limbs that were held in an odd mix of sprawled hind limbs and raised forelimbs. It had a long neck and a proportionately small head with remarkably sauropod-like jaws and teeth.
Azendohsaurus used to be classified as a herbivorous dinosaur, at first as an ornithischian but more often as a "prosauropod" sauropodomorph. This was based only on its jaws and teeth, which share derived features typically found in herbivorous dinosaurs. The complete skeletal material from Madagascar, however, revealed more basal characteristics ancestral to Archosauromorpha and that Azendohsaurus was not a dinosaur at all. Instead, Azendohsaurus was actually a more primitive archosauromorph that had convergently evolved many features of the jaws and skeleton shared with the later giant sauropod dinosaurs. It was found to be a member of a newly recognised group of specialised, mostly herbivorous archosauromorphs that was named the Allokotosauria. It is also the namesake and typifier of its own family of allokotosaurs, the Azendohsauridae; initially the only member, the family now includes other similar allokotosaurs, such as the larger, horned azendohsaurid Shringasaurus from India.
Several other groups of archosauromorphs also adapted to herbivory in the Triassic, sometimes with dinosaur-like teeth that also caused confusion in their classification. Azendohsaurus is notable, however, for also convergently evolving a similar body shape to sauropodomorphs in addition to its jaws and teeth. Azendohsaurus and sauropodomorphs likely independently evolved to fill a similar ecological niche as long-necked, relatively high browsing herbivores in their environments. However, Azendohsaurus predates the large Late Triassic sauropodomorphs it resembles by several million years, and did not evolve similar body plans under the same environmental conditions. It may then have been one of the first herbivores to fill the high-browsing role that only large sauropodomorphs were thought to occupy during the Triassic, expanding the known ecological diversity of herbivorous archosauromorphs outside of dinosaurs in the Triassic Period. Azendohsaurus is also significant as it may be one of the earliest endothermic archosauromorphs known, and suggests that a warm-blooded metabolism was ancestral to the later archosaurs, including the dinosaurs.