It was originally described as coming from the Allen Formation but subsequent research proved the remains were actually found in the older Anacleto Formation (part of the Neuquén Group) of Rio Negro Province, Argentina.
Den hittades i Allen-formationen, men påföljande analyser bevisar att kvarlevorna faktiskt hittades den äldre Anacleto-formationen (en del av Neuquen-gruppen) i Rio Negro-provinsen, Argentina.