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Hi there fellow list members. Just thought
I'd post a bit of information I've come across recently that most people may not
be aware of.
First a bit about an early pygostylian that's been
misplaced. Otogornis is not an enantiornithine, but is actually an
ornithurine. This comes from a paper by Kurochkin that was mentioned by
Tim Williams back in June, but doesn't seem to have changed the genus' placement
in many peoples minds. The evidence is quite good, including the
"normally" developed scapulocoracoid joint, as opposed to the "backwards" joint
of enantiornithines. Kurochkin views Otogornis as being most closely
related to Ambiortus in a Ambiortiformes.
reference- Kurochkin, Evgeny N. (1999). The
relationships of the Early Cretaceous Ambiortus and Otogornis (Aves:
Ambiortiformes). Smithsonian Contributions to Paleobiology. 89:
275-284.
There are also several new findings announced in
the recently published Dinosaurs of New Mexico that should interest some
readers.
The supposed squamosal of Zuniceratops is actually
a therizinosauroid ischium. More of the specmen is known and is currently
under preparation and description.
The "Aublysodon" skeleton described by Lehman and
Carpenter (1990) is actually Daspletosaurus. The premaxillary tooth is
serrated, contra Lehmen and Carpenter. This means no postcrania can be
confidently assigned to Aublysodon. Carr and Williamson suggest
that Aublysodon remains (including A. "molnari") are actually from juvenile
tyrannosaurids, pointing out the morphological features used to separate them
vary ontogenetically. What does this mean for Shanshanosaurus?
Juvenile Tyrannosaurus bataar anyone? The authors also do a detailed study
that show tyrannosaurids cannot be distinguished by denticle counts, as
they vary with size and position on the tooth. The only exception is
Tyrannosaurus teeth over 27 mm long, which have lower denticle counts than
others of similar size. Time to look into denticle
and crown morphology I guess....
Lucas and Sullivan find the holotype of Alamosaurus
has no autapomorphies, so is a nomen dubium. They hypothesize more than
one titanosaurid inhabited Late Cretaceous North America.
Pachycephalosaurs are due for a reevaluation.
Sullivan finds that besides "Stegoceras" brevis and "S." edmontonensis, which he
refers to Prenocephale, Stegoceras validum should be split up into several
genera. On the other hand, Ornatotholus is probably synonymous with S.
validum sensu strictu. Also, Gravitholus resembles Prenocephale, but is
not congeneric, and will be reanalized soon....
Also, good cases made for the synonymization of
Naashoibitosaurus and Anasazisaurus with Kritosaurus. Did you know that
the nasal IS preserved in the holotype of Kritosaurus, despite what many have
said? Now if only Gryposaurus, Hadrosaurus and that Argentine gryposaur
were analized....
And I just may have something regarding "Aniksosaurus" to say in the near future. We'll have to wait and see if my hunch is correct.... Mickey Mortimer
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