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<<Can anyone tell me if they agree that the similarity of *Torvosaurus'*
and *Cryolophosaurus'* lachrymals means that Torvo can be included in
the Carnosauria as on the same cladistic branch of *Cryolophosaurus* and
<Could be, but what does the weight of the evidence say? Single
character resemblances are interesting, but one must figure out a) are
the resemblances derived or primitive and b) what is the distribution of
other features in the anatomy.>
*Sinraptor* has an otherwise unspectacular lachrymal, when compared to
*Allosaurus* and *Yangchuanosaurus*. I refer to the flange at the base,
very long and occlusive of the jugal from the antorbital fenestra. Such
a flange is seen in *Allosaurus*, *Yangchuanosaurus*, and to a less
occlusive state, *Monolophosaurus*. It appears the same condition [long
flange] is evident in *Acrocanthosaurus*, though the jugal appears to be
incomplete in the photo I've seen of the skull (right side).
This may be synapomorphic, though my case is not very strong.
*Ceratosaurus* has an occluded jugal, but the lachrymal flange is very
short, and neither the skulls of other "megalosaurs" like *Edmarka* or
*Megalosaurus* seem to possess the bone.
All add something, though. The dentary tooth of the type of
*Megalosaurus* is less strongly curved (very strait, indeed) than
*Torvosaurus'* is, and the curve is similar enough to *Yangchuanosaurus*
and *Allosaurus* that it supports a carnosaur-link. And besides, wasn't
Torvo already plausibly connected to the Carnosauria, at least as an
<The skull of Cryolophosaurus is pretty puzzling as currently described,
particularly the squamosal-postorbital-jugal contact (which, in all
right-thinking theropods, do NOT form a single contact in the middle of
the infratemporal fenestra!!). I haven't seen the postcranial material,
so that's (obviously) more difficult to judge...>
That's a shame---many similarities I've noted between currently
recognized taxa within Carnosauria are found on the pelvis. The humerus
of the *Torvosaurus*, though, does have some similarities with
*Allosaurus*, and *Afrovenator*'s forearm is also somewhat similar.
It _IS_ a most interesting skull, and I've just finished restoring it on
paper, and will soon scan it in to my computer, along with a redraw of
the *Monolophosaurus* skull from Zhao & Currie, 1993.
<In most recent studies, true carnosaurs (Allosauroidea and closely
related forms) are more closely related to coelurosaurs than either
group is to Torvosaurus. Carnosaurs and coelurosaurs share a maxillary
fenestra, pneumatic lacrimals, and other features not known in
These may be derived features; but I agree that these are some of the
prime characters detrimental to my hypothesis. Still would like to see
the postcrania . . . My library's shut down for a week, so I can't get
to some materials, but can you tell me if the October 1994 National
Geographic issue's article on the frozen carnosaur has any photos? I
also heard a Sunday Chicago Times article had published photos of the
skeleton and skull.
<However, it is possible that later studies might reveal features
uniting allosauroids and Torvosaurus within Carnosauria. Such is the way
of phylogenetic analysis (or any science, for that matter: subject to
revision based on new data).
I think that Bakker et al.'s and Sereno's suggestion that
Eustreptospondylus is closely related to Torvosaurus may have some merit
based on current data. Unfortunately, both are less complete than one
(okay, I) would like... :-(>
This idea I concur with, as my clades you've seen show, with
*Eustreptospondylus* as very basal (and probably the progenitor) of the
Carnosauria . . . and not only is he incomplete, but juvenile. My only
problem is that *Gasosaurus* and *Kaijiangosaurus* may be more
primitive, as the Dashanpu has not been accurately dated, as far as I've
read in _Encyclopedia of Dinosaurs_ and _PDW_ and other texts.
Jaime A. Headden
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