Despite its large size, Gualicho's forelimbs were the size of a human child's. Like T. rex, it had just two digits: a thumb and forefinger.
Gualicho somewhat resembles the dinosaur Deltadromeus, which was a leggy meat-eater with slender arms from Africa. Makovicky and his colleagues therefore think that it was closely related to Deltadromeus.
"Gualicho is kind of a mosaic dinosaur; it has features that you normally see in different kinds of theropods (two-legged, bird-like dinosaurs)," Makovicky said. "It's really unusual -- it's different from the other carnivorous dinosaurs found in the same rock formation, and it doesn't fit neatly into any category."
Shinya had this to say about her namesake dino: "We found Gualicho at the very end of the expedition. Pete joked, 'It's the last day, you'd better find something good!' And then I almost immediately was like, 'Pete, I found something.' I could tell right away that it was good."
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