Name: Pisanosaurus mertii
Name Meaning: Merti & Mr. Pisano’s lizard
First Described: 1967
Described By: Casamiquela
Classification: Dinosauria, Ornithischia, Pisanosauridae
My Twelfth Favorite Dinosaur!
Oh look another basal dinosaur what a surprise. Pisanosaurus is considered to be the basalmost ornithischian, or at least the basalmost one known to date. It lived between 228 and 216.5 million years ago in the Norian age of the Late Triassic period. It was found in the Ischigualasto Formation in Argentina and it was a small, lightweight, bipedal herbivore about 1 meter long. Its classification has been under a lot of debate but the current consensus is that it is the oldest known ornithischian. It is only known from a single skeleton that is known from a partial skull and some teeth, some vertebrae, and other bones including part of the pubis, allowing for its classification. Given the synapomorphic character of protofeather/feather like integuments it probably was covered with them in at least some parts of its body. It lived in a volcanically active floodplain that was covered with forests and was warm and humid, but subject to seasonal rainfalls. It probably ate the vegetation of the area which consisted of ferns, horsetails, and conifers. Its major predator was probably Herrerasaurus, which was the most common predator in the area. Pisanosaurus lived right alongside therapsids, rhynchosaurus, dicynodonts, traversodontids, rauisuchians, archosaurus, Saurosuchus, and Eoraptor as well as Herrerasaurus. Herbivorous dinosaurs such as Pisanosaurus were definitely in the minority.
Shout out goes to anonbinarywolf!