Dinosaurs recovered from northern South America are rare so "Thief of Tachira" (Tachiraptor admirabilis) is all the more noteworthy. It's only the second known dinosaur from what is now Venezuela.
The new dino, described in the journal Royal Society Open Science, measured just 6.6 feet long, but it had a ravenous craving for meat.
"Tachiraptor probably preyed upon any smaller animal he could catch," lead author Max Langer explained to Discovery News.
Langer, a paleontologist at the Universidade de Sao Paulo, and his colleagues discovered Tachiraptor's remains in the Venezuelan state of Tachira. The dinosaur represents both a new genus and species.
The remains, based on radiometric dating of rocks at the site, date to 200 million years ago. This corresponds to the earliest phase of the Jurassic Period.
The date and location of the fossils help to explain how carnivorous dinosaurs spread around the world after the end of the Triassic mass extinction. That devastating event wiped out an estimated 84 percent of all species, including many dinosaur groups.
The ancestors of "Thief of Tachira," however, were clearly a hearty lot that survived the onslaught, possibly triggered by volcanic eruptions, extreme temperatures and falling sea levels. Helping the spread of dinosaurs after the extinction event was the fact that most of the continents at the time were joined together to form the supercontinent Pangaea.
Langer said that "an equatorial belt including southern North America, northern South America and northern Africa were bordered to the north and south by extensive deserts." The more hospitable belt "played a pivotal role in the radiation of the different dinosaur groups."
Langer explained that within the belt region conditions were more humid and tropical. He and his colleagues believe the area where Thief of Tachira was found was then forested, with rivers nearby. In short, it would have been a quite comfortable place for a dinosaur to live.
Life would not have been quite so pleasant for Venezuela's other known dinosaur, Laquintasaura. Langer suspects that Tachiraptor spent a lot of time hunting this smaller plant-munching dinosaur, which was about half of the predator's size.
Paul Barrett, a Natural History Museum paleontologist who led the discovery of Laquintasaura, told Discovery News that Laquintasaura probably lived in herds, offering some protection from bloodthirsty Thief of Tachira.
Barrett said that despite the end of the Triassic mass extinction, "dinosaurs bounced back quickly after this event. It is fascinating and unexpected to see they lived in herds, something we have little evidence so far in dinosaurs from this time."
It is uncertain whether or not the new carnivorous dinosaur lived solo or in a herd. Predators even today tend not to live in herds.
As for why so few dinosaurs have yet to be discovered from Venezuela and northern South America in general, Langer had a simple and short answer: few paleontologists are conducting research in the area.
Read more at Discovery News
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