The first dinosaur found in Venezuela is one of the world's oldest, living right after the major extinction event at the end of the Triassic Period.
The 200-million-year-old dinosaur, described in the latest issue of the Proceedings of the Royal Society B, has been named Laquintasaura venezuelae. The name was inspired by where it was discovered, the La Quinta Formation in Tachira State, Venezuela.
"Laquintasaura was a small bipedal dinosaur about 1 meter (3.3 feet) long," lead author Paul Barrett, a paleontologist at the Natural History Museum in London, told Discovery News. "It was probably largely herbivorous, but its slightly curved and elongated teeth hint at occasional omnivory. The teeth are the most distinctive feature of the new dinosaur, as their elongated, curved outline and striated surfaces are unique."
"There are many surprising firsts with Laquintasaura," Barrett said. "Not only does it expand the distribution of early dinosaurs, its age makes it important for understanding their early evolution and behavior."
Another important first for this dinosaur is that it provides the earliest likely evidence for social behavior in "bird-hipped" dinosaurs (ornithischians). The group includes species such as stegosaurus, triceratops and iguanodon.
Fossils from at least four Laquintasaura individuals were found together, with the dinosaurs ranging in age from 3 to approximately 12 years old. The researchers suspect that the dinosaurs were "gregarious" and lived together in a herd. It looks like they died together too, although the cause of their death remains a mystery.
Laquintasaura's later Cretaceous relatives were social animals, so it's theorized this characteristic emerged early among bird-hipped dinosaurs.
"It is fascinating and unexpected to see they lived in herds, something we have little evidence of so far in dinosaurs from this time," Barrett said.
So why did it take so long to find a dinosaur in Venezuela? Researchers thought the region around 200 million years ago would have been too inhospitable to support a dino, or for that matter any relatively large animal.
Because Laquintasaura munched on ferns -- and probably insects and other small prey -- suggests that Venezuela supported a richer ecosystem than was previously thought.
Another unexpected aspect is that this new dinosaur emerged just 500,000 years ago -- a veritable drop in the geological time bucket -- after the Triassic-Jurassic extinction event that led to the disappearance of at least half of Earth's species at the time.
"This shows that dinosaur evolution was either relatively unaffected by the extinction, or that they were quick to recover in its aftermath," Barrett said.
Paleontologist Marcelo Sanchez-Villagra of the University of Zurich said the new dinosaur is an important find.
"The early history of bird-hipped dinosaurs is still very patchy as so few of them have been found," Sánchez-Villagra said. "This early species plays a key role in our understanding of the evolution, not only of this group, but of dinosaurs in general."