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Re: Carniadactylus paper and pterosaur ontogeny

DP: Unfortunately Fabio did not test MPUM 6009 as a separate taxon to see if it would indeed nest with the former E. rosenfeldii. DM: This would require scoring all ontogeny-related characters as unknown for MPUM 6009. How many would that leave?


You may be a little behind the times, David. Pterosaurs and their nonvolant sisters experienced isometric growth. If two taxa are the same species, no matter their ontogenetic age, they would nest as sisters. If MPUM 6009 nests elsewhere, closer to another taxon, it is not a sister. So, contra tradition, there are NO ontogeny-related characters. All prior assumptions were just that, assumptions. That includes tooth count, orbit/rostrum ratios, tiny pedal phalanx ossification, scapulocoracoid fusion, sacral fusion, etc. Put them all into a cladogram and your eyes will pop. Maisano 2004 in JVP provides modern analogs.

All the above is proven by adding embryo and hatchling Pterodaustro to any cladogram that has Pterodaustro adults. You'll find they nest as sisters. Although, it is of considerable interest that the one good complete skeleton of Pterodaustro (adult) has distinct pedal phalanx and metatarsal proportions from the Pterodaustro hatchling. Maybe NOT conspecific.

A privately-owned Pteranodon, 1/4 the size of P. marshi (skull) and P.ingens (post-crania) has the proportions of an adult including a fused extensor tendon process. It nests with these, some of the largest known specimens. Unfortunately, due to its provenance, it will never be published, but interested parties can obtain a pdf report with images by contacting me.

Same goes for Bennett's "juvenile" Anurognathus. Unpublishable because it is privately held but a pdf is available through me. It is a new genus with a pancake-skull after reconstruction. It has small eyes where they belong, in the back half of the skull. Every bone was found and found to be similar to those in other pterosaurs, contra Bennett's guesses.

The only pterosaurs we KNOW that are NOT adults are those inside eggshells. All other suspects need to be placed into a phylogenetic context to test their nesting. BTW, Bennett from 1991 on notes the bone texture issue appears on immature and mature Pteranodon specimens of the same size.

If you have any other data, please share it.

David Peters
St. Louis