If you keep an eye on the wacky world of zoological nomenclature, you’ll know that earlier this year Emanuel Tschopp and Octávio Mateus published a petition to the International Commission on Zoological Nomemclature, asking them to establish Diplodocus carnegii , represented by the ubiquitous and nearly complete skeleton CM 84, as the type species of Diplodocus . That is because Marsh’s (1878) type species, YPM 1920, is a pair