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Utahdactylus is not a Pterosaur
Not sure what unambiguous conditions led the authors to conclude this, but
reading Bennett's comments detailing his impressions, and getting scans of
the figures from Mickey Mortimer, I am aghast that the authors did not see
what was likely the most "obvious" interpretation: *Utahdactylus* appears
to comprise vertebrae of a sauropod. Three vertebrae, CEUM 32588, are
shown in sagittal section where the trabecullar structure of the centra
and neural arches are exposed. The centra are somphospondylous, very
complex in their camellae, and the neural arches are, by contrast,
polycamarate (using the terminology of Wedel et al., 2001, _Acta Pal. Pol.
45(4)). This condition occurs in many neosauropodans, with a
somphospondylous centrum in macronarians. The centra are short, about as
long sagittally as twice their caudal height, and what have been
identified as dorsals (figs. 4-5) may be short cervicals. Another slab
refered to *Utahdactylus* (figs. 6-7), has a series of long slender bones
that may be cervical ribs, and there is a positive cast of a long
structure that may be the impression of a ventral cervical centrum. Other
elements include a scapulocoracoid (figs. 10-11), and rather than
contradicting this, it is easily corroborated as such, only the authors'
id can be reversed: their coracoid is a scapular blade, and their proximal
scapula is a partial coracoid, where the glenoid is clearly exposed and
the dorsal margin of the articulated (not fused) elements are missing. A
rib and dorsal vertebral centrum not in section are associated dorsal to
the element. Finally, figs. 8-9 are the positive casts of a long element
identified as a "humerus" with "scapulocoracoid" fragment, though how this
conclusion was garnered I know not. They in fact appear to be pelvic in
nature, and possibly pubic where one end bears a likely ambiens process;
an ischiadic identity is also possibly, and the "process" may be the iliac
This is, as Mickey Mortimer tells me as I write it, a "helluva misnomer"
... *Utahdactylus* is a sauropod? What is clear is it is not a pterosaur,
and S. Chris Bennett et al. may have the "real" first pterosaurs from
Now, which taxa does it resemble as a sauropod? can it be referred to
another taxon, or will *Utahdactylus* become one of the oddest sauropod
names ever? First off, the most diagnoistic elements to this comparison
are the vertebrae, which are fairly short, camellate in the centra, and
camarate in the neural arches. This morphology is known in
*Haplocanthosaurus* and some macronarians such as brachiosaurs, only the
centra is far more camellate (somphospondylous) than in "brachiosaurids."
Perhaps it is referrable to *Haplo.* or *Brachio. altithorax,* perhaps
unique. Maybe Matt Wedel, if he's still monitoring this list, could help
as this is relevant to his dissertation research.
Jaime A. Headden
Little steps are often the hardest to take. We are too used to making leaps
in the face of adversity, that a simple skip is so hard to do. We should all
learn to walk soft, walk small, see the world around us rather than zoom by it.
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