Sauropods are Mesozoic puzzles. These long-necked, large-bodied dinosaurs pushed evolutionary innovation to the extreme, and even the simplest aspects of their biology are confounding, oft-debated subjects. For one thing, how could these dinosaurs occupy such a range of body sizes – over 100 feet long among the largest – with tiny, peg-like teeth? These dinosaurs couldn’t chew at all, but must have horfed down vast quantities of greens to fuel their fast-growing bodies. The distinctive, simple teeth of sauropods underscore how strange these animals truly were, and an isolated tooth found in Argentina hints at the presence of what may be an unknown, unusual sauropod.

Universidad Nacional de Río Negro paleontologist Rodolfo García describes the simple, cylindrical tooth in an in-press