I was musing this morning, as I often do, about pterosaurs, when a thought struck me. Is "Rhamphorhyncoidea" a natural group? Supposedly it forms a sister group to the Pterodactyloidea, but what if pterodactyloids are derived directly from rhamphorynchoids? Pterodactylus is still, as far as I know, the earliest known pterodactyloid, and it doesn't show up until the Late Jurassic, whereas rhamphorhynchoids are known since the Late Triassic, and in all likelihood, the group originated well before that. Were pterodactyloids an actual sister group, that would imply a very long ghost lineage leading back to the origins of the Pterosauria.
But then you look at anurognathid pterosaurs, who are "short-tailed rhamphorhynchoids," and wonder where that group perhaps shares a more direct relationship with pterodactyloids. Were that the case, then "Rhamphorhychoidea" would be paraphyletic. I'm not suggesting that some rhamphorhynchoids don't share some common ancestry. Rhamphorhynchus and Dorygnathus are certainly sister taxa. Dimorphodon and Peteinosaurus seem close enough. Certainly the scaphognathines form a monophyletic clade. But how do all these smaller groups relate to one another? What if rhamphorhynchoids form a stepwise progression leading to Pterodactyloidea, much like we know understand Prosauropoda to be a paraphyletic grade of animals leading to Sauropoda?
The name "Rhamphorhynchoidea" would have to be abandoned, unless we start calling Pteranodon a pterodontid ornithocheiroid pterodactyloid rhamphorhyncoid pterosaur. That wouldn't work.
Has any work been done on the interrelationships between the various families of the Rhamphoryhncoidea and that group's relationship to the Pterodactyloidea? And while we're on the subject of pterosaurs, does anybody have a good paper detailing Nyctosaurus' reindeer antler? I'm restoring that monster for the upcoming Archosauria art show.