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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