The new megaraptoran dinosaur: Rinconraptor pipoae

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Transcript:

There's a brand new megaraptoran from Argentina, and depending on how much you know about megaraptorans, you're either going to be really upset about how fragmentary it is or really excited about how complete it is. So, for whatever reason, megaraptorans just don't preserve that well. They're pretty much exclusively known from fragmentary remains, and not a single complete skeleton has ever been found. That said, there have been enough remains found that paleontologists have a pretty firm grasp of what they looked like. They didn't just look like giant raptors, like Velociraptor. They were their own group of predatory theropods, potentially more closely related to dinosaurs like Tyrannosaurus than to anything like Velociraptor. They were medium-to-large, pretty lightly built theropods, but the really standout feature are their arms. And unlike a lot of theropods, they're not famous for having tiny arms. They're famous for having large, strong, heavily clawed arms. And this new species looks like it follows that body plan, being compared to dinosaurs like Mapusaurus. Meet Rinconraptor pipoae, the new 23-ft megaraptoran from late Cretaceous Argentina. Obviously, like I said, it's known from fragmentary remains, but by megaraptoran standards, it's not really that bad. It's known from multiple vertebrae, a partial ulna, partial tibia, partial humerus, and even a toe bone. So, small pieces, but small pieces from all over the body, which made it easier for paleontologists to compare it to its close relatives and find where in the family it actually belongs. Not only were paleontologists able to accurately place it within the megaraptoran family tree, they were also able to spread that tree out further, reinforcing the potential relationship between megaraptorans and Tyrannosaurus. As usual, if you want more information, here's the source.

Ariel H. Méndez, Ariana Paulina-Carabajal, Leonardo S. Filippi, Federico A. Gianechini, Javier González-Dionis, Lucía F. Vettorazzi, E. Emanuel Seculi-Pereyra, Karen Ulloa-Guaiquin, Francisco T. Barrios, Penélope Cruzado-Caballero, Flavio Bellardini, M. Elena Previtera, Hugo Valdez, Arturo M. Heredia, Magalí Cárdenas, Alberto C. Garrido, Do-Kwon Kim, and Yuong-Nam Lee. New Megaraptorid from Patagonia Expanding the dinosaur diversity of the Cerro Overo–La Invernada area (Bajo de la Carpa Formation, Santonian), Northern Patagonia: Description of a new species and additional megaraptorid remains.
Article number: 29.3.a41 doi: 10.26879/1738 Paleontological Society, October 2026

Meet Rinconraptor pipoae! The newest Megaraptoran dinosaur from Cretaceous Argentina. Like most megaraptorans, this dinosaur is only known from partial remains, but paleontologists have been able to get plenty of information from them.

Episode 366

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