Howse and Milner (1995)
described a spoonbill rostrum lacking teeth in place. They correctly compared it to the much smaller pterosaur Gnathosaurus and called their English find Plataleorhynchus stretophorodon (Fig. 1, BMNH R 11957). As you can see, it was much bigger.
Howse and Milner did not realize they were looking at the rostrum in dorsal aspect. And for that reason, perhaps, they did not correctly figure the lateral extent of the premaxilla (Fig.1). No pterosaur has more than four teeth erupting from the premaxilla and Plataleorhynchus was no exception. So the premaxilla had a very short anterior exposure, rather than encompassing the entire spoonbill, as Howse and Milner interpreted the fossil from firsthand observation.
Howse and Milner did correctly note differences in the rostral shape and relative tooth size between Plataleorhynchus and Gnathosaurus, and also correctly noted that no other known pterosaur was closer. So, by this evidence, some mistakes don’t matter in the end.
Like Gnathosaurus and other ctenochasmatids,
Plataleorhynchus had dorsally expanded maxillae that contacted one another over the premaxilla aft of the spoonbill. Due to their orientation mistake, Howse and Milner identified the second dorsal appearance of the premaxilla as the palatine.
Howse and Milner thought the palate had a horny pad based on the rugosity that was exposed. That rugosity, (here considered dorsal) is also present in Gnathosaurus, but not as prominent. The reason or origin for the rugosity on the dorsal tip of Plataleorhynchus is difficult to explain, but may be related to the further extent of the maxillae and perhaps some sort of small horny crest.
the palatal extent of the premaxilla is much smaller in the comparable Gnathosaurus than envisioned for Plataleorhynchus by Howse and Milner. In Gnathosaurus I’m not sure how the teeth were not shaken loose. The roots appear to be exposed on the palate (Fig. 1). They must have been held in place by soft tissue.
Considering this mistake,
much has been made about the value of firsthand observation versus the examination of photographs and illustrations. Paleontologists are fond of dismissing interpretations made in the absence of the fossil itself. They forget that most of the credit or blame for a discovery happens not in the lab, but between the ears. You have to see things correctly from the start or all the dominoes start to fall the wrong way. Mistakes can happen to anyone (including yours truly). Howse and Milner 1995 (Fig. 1) is another example of a firsthand observation that went awry based on one initial mistake. And that was an easy one to make with that odd spoonbill rostrum. It was flat on both sides.
Like Cope vs. Marsh back in the day, I am, once again metaphorically, “putting the skull on the other end of the skeleton” by flipping over the rostrum of Plataleorhynchus. The correct response, of course, should be curiosity or gratitude, not embarrassment, anger or dismissal. However, if anyone out there thinks the rostrum exposure is still palatal, I’d like to hear from you.
Howse SCB and Milner AR 1995. The pterodactyloids from the Purbeck Limestone Formation of Dorset. Bulletin of the Natural History Museum London (Geology)51:73-88.