The Pisanosaurus was discovered in the Ischigualasto Formation in Argentina in 1962. This tiny dino is an early ornithischian dinosaur, named for its bird-like hips. Pisanosaurus was about the size of a chicken with strong, quick back legs.
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Some Quick Facts about the Pisanosaurus
| Name | Pisanosaurus (meaning “Pisano’s Lizard”) |
| Type of dinosaur | Ornithischia |
| Territory | Woodland areas with plenty of water and volcanic activity, La Rioja, Argentina, South America |
| Size | 3.3 feet long, 1.5 feet tall |
| Color | Greenish, scaly with feathers |
| Interesting Characteristics | Long hand bones, open hip sockets, and strong hind limbs. Many scientists believe that Pisanosaurus would’ve had feathers like other Ornithischian Dinosaurs |
| Diet | Herbivore |
| Major Threats | Natural disasters and larger predators |
The Pisanosaurus was a tiny dinosaur that lived around 228 million years ago! It was found in the Ischigualasto Formation of Argentina, where dinosaurs like the Herrerasaurus, Eoraptor, and Panphagia were found.
While paleontologists have gone back and forth on the Pisanosaurus’s classification, the Pisanosaurus is still considered a primitive Ornithischian or “bird-hipped” dinosaur.
Where Did the Pisanosaurus Live?
The Pisanosaurus was found in the Ischigualasto Formation. This is a fossil hotspot, where many dinosaurs from the Late Triassic of Argentina have been found. During Pisanosaurus’s lifetime, this area was full of dense vegetation like ferns and conifer trees.
This area of prehistoric South America had a lot of flooding and volcanic activity. Because of this, mud and lava were swept over the Pisanosaurus and other dinosaurs when they went extinct.
Today this area looks more like the surface of the moon than the rich forests of more than 200 million years ago. But the mudslides and lava preserved the fossils, trapping them together and giving us a glimpse of the dinosaurs that once lived together in this part of the world.
Did Birds Descend from the Pisanosaurus?
Birds are not descendants of the Pisanosaurus or other ornithischian dinosaurs. Birds evolved from the theropod saurischian dinosaurs, which include the Tyrannosaurus rex! In fact, even though we have modern-day animals like crocodiles and alligators that look like dinosaurs, birds are the only direct descendants of dinosaurs!
Even though crocodiles and alligators are not descended from dinosaurs, they are actually close relatives to birds. Crocodiles and alligators come from a group that came before dinosaurs called Archosaurs. Archosaurs are not related to dinosaurs.
It’s hard to believe that a pigeon has more in common with T. rex than an alligator, but it’s true!
What Kind of Dinosaur is the Pisanosaurus?
The Pisanosaurus is an ornithischian dinosaur, which is a dinosaur with bird-like hips. This group includes dinosaurs like the Triceratops. Because the Pisanosaurus is so unique, it has its own family classification: Pisanosauridae. But scientists aren’t sure if Pisanosaurus is truly an ornithischian dinosaur, or something else.
It was Jose Bonaparte who first noticed anomalies in the Pisanosaurus in 1976. Later paleontologists like Federico L Agnolín would question whether the Pisanosaurus was really a non-dinosauriform silesauridae. Another scientist, Paul Sereno, thought the Pisanosaurus’s unique features might be the result of a birth defect.
The scientific community is still divided on Pisanosaurus. This unique dinosaur doesn’t really fit in 100% with ornithischia or silesaurid. In fact, some paleontologists think the Pisanosaurus might even be a transitional taxon between silesaurids and ornithischia altogether!
For now, Pisanosaurus remains an ornithischian dinosaur, a group of dinosaurs that survived through most of the Mesozoic era into the Jurassic period. The holotype (single specimen) of the Pisanosaurus is still being studied today.
And with each new dino discovery, paleontologists learn more about all dinosaurs. Who knows, in a few years, the Pisanosaurus might prove to be the key to unlocking new and exciting information about dinosaurs!