Here, I'm referring to another Triassic reptile, the aetosaurs, who are contemporaneous with the sheep-lizards and the pig-lizards mentioned before.
And just like the others mentioned, the aeotosaurs are easily confused with the dinosaurs.
To be quite frank, at a quick glance I don't blame anyone for confusing the two.
The aetosaurs are actually archsaurs, the same group as the rhychosaurs (pig-lizards). The archosaurs were a crocodile-like group who are ancestral to both crocodilians and dinosaurs both. Terms such as pseudocrocodiles and paracrocodiles have been mentioned. Sometimes their armor has been likened to the much later ankylosaurs (which I didn't know is grouped closely with stegosaurs, although I see why).
It's not entirely clear that the "armor" was used primarily for defense, nor is their cat-like posture universally accepted. These ideas are widely thought, however.
And since I am talking about Triassic fauna, don't forget the croc-sized salamanders and the early dinosaurs of this era, such aspisanosaurus. I think it's terribly funny that an especially small dinosaur was named 'pisant lizard', but as it turns out it is just a coincidence of the last name of a famous Argentine paleontologist was honored with his own dino.
Cool link about these guys: