> Megalancosaurinae = Drepanosaurus + Megalancosaurus.
Wrong under ICZN Article 36.1. http://www.iczn.org/iczn/includes/page.jsp?article=36 When Drepanosauridae was coined, Drepanosaurinae, -ini, -ina, and -oidea were automatically coined with it, so Drepanosaurinae already exists and has priority over Megalancosaurinae. In other words, whichever subfamily of Drepanosauridae that contains *Drepanosaurus* must be called Drepanosaurinae. It does not matter at all whether the name Drepanosaurinae has ever been used in a publication.