Fossil Pterosaur Teeth Issues
The number of teeth sold by dealers (especially from North Africa) as pterosaur teeth is staggering. Many are not pterosaur teeth at all, but are passed off as pterosaur to attract a better sale price. Teeth will be broken or fall out during feeding or fighting, especially in the marine reptiles and crocodiles. Observation of pterosaur fossil jaws suggests that pterosaurs seldom loose teeth in this way as most species would grab small prey and swallow it whole. Also, with their light weight skeletons, pterosaurs would be likely to avoid fighting, as most modern bird species do today.
Many species of marine reptiles have teeth that are single cusped and recurved in a similar way to those of pterosaurs. The teeth vary along the jaw in both size and shape. It is inevitable that some of the teeth will look like pterosaur teeth to an inexperienced eye, and even to an expert if the tooth is broken and seen in isolation. Juvenile animals may also have smaller and less well developed teeth. Some species of fish also have fang like teeth that may be confused with those of pterosaurs. If the fish teeth are subjected to microscopical analysis they can usually be identified as fish teeth.
A scientist will err on the side of caution when viewing teeth in isolation, looking to identify the tooth as the most common fossil option for a given sediment. A fossil dealer will be more inclined towards the most profitable identification in a free enterprise market. If a tooth looks like a pterosaur tooth it will make a better price as a pterosaur tooth. There are also some very reputable dealers who do not follow this trend.
Things to look out for that will identify a non-pterosaur tooth.
Things to spot about real pterosaur teeth.
The section of the tooth will have a very thin enamel layer around the dentine in real pterosaur teeth. Marine reptiles tend to have a much thicker enamel on the tooth. Some Rhamphorhynchoids do not have enamel on the buccal or lingual surfaces of the lower tooth.
Look for wear facets on the teeth. They should be smoother than the rest of the tooth surface and they will correspond to polishing wear from an opposing tooth. This is often seen on the teeth at the front of the jaw in pterosaurs, but it is not diagnostic of a pterosaur tooth on its own. If wear is present, it should expose dentine. This is not always shown where the whole tooth has been replaced with the same mineralization.
The best way to identify an isolated pterosaur tooth is to compare it to a reference collection in a university or a museum. Since pterosaur specimens are rare, this may not be practical. A review of scientific literature can be a good guide, but this is only practical if you have a working knowledge of pterosaur material. Consulting an expert in the field is the best alternative and this can usually be done at most national palaeontological collections.
If you chose to consult an expert by E-mail - include photographs from the side, front and root to show the curvature, any lengthwise detail and the root cross section. Information about where it was found and the geology and age of the find would also be very useful.