Opisthocoelicaudia skarzynskii

A Late Cretaceous titanosaur from Mongolia, Opisthocoelicaudia is known from a well-preserved skeleton lacking only the head and neck, type specimen MPC-D100/404. As luck would have it, another titanosaur (Nemegtosaurus) was only known from a skull. It has been suggested that they may be different specimens of the same animal, and recent discoveries have mostly backed this up, in which case Opisthocoelicaudia would be subsumed into Nemegtosaurus. Not all authors agree, so until more overlapping material is found to support it I am still labeling this Opisthocoelicaudia…but the head definitely follows Nemegtosaurus!