1.37" (3.5 cm) Diplodocidae (Sauropod) tooth from the Isalo Ill formation of Madagascar. The Isalo Ill Formation is 168-165 million years old.
Prosauropod teeth were serrated but those serrations were lost over time and were gone by the time Diplodocus existed. This tooth has faint remnants of the prosauropod serrations, showing a transition in teeth from prosauropod to diplodocid.
