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Re: STONESFIELD THEROPODS AGAIN
RE: OUM J13506. The original Megalosaurus bucklandii,
as described by Buckland, did not have a maxilla
associated with it, J13506 never mentioned, nor
described, by Buckland himself. The character traits
you cite are genuine, and, in my mss.-in-revision, I
have removed J13506, the left maxilla, and a similar
left maxilla J13559, from the hypodigm of M.
As I have mentioned previously, M. bucklandii consists
of a disarticulated skeleton of one individual (this
was something Sam Welles was adamant about with me for
longer than I can remember, as he did not believe
there was a twin individual Buckland was wrestling
with in 1824): the lectotype J13505, rostral right
dentary; and: 13577, last dorsal; 13576, sacrum,
13579, proximal caudal; 29881, right ilium; 13563,
cranioproximal end + shaft of a right pubis; 13565,
left ischium; 13561, right femur; 13572, left
Over the years, other specimens were collected at
Stonesfield, and these are described, compared, and
illustrated in my mss.-in-revision (not all of them
were M. bucklandii, to be sure). But Sam was never
sure if any of them were associated with Buckland's
original skeleton, so he restricted the
lectotype/kleptotype to the Buckland skeleton
described in 1824.
There were, indeed, other theropods contemporaneous
with M. bucklandii, especially Metriacanthosaurus
brevis, whose type left ilium, BMNH 31811, differs
from Megalosaurus bucklandii in its great height and
shortness (diagnostic for Metriacanthosaurus).
--- firstname.lastname@example.org wrote:
> This is coming weeks and weeks late (sorry) but
> wanted to
> get it out of the way. Many posts ago we discussed
> here the
> fact that the Stonefield Slate Fm maxilla OUM J13506
> appears fundamentally different from those of
> megalosaurids (_Eustreptospondylus_, _Torvosaurus_
> most importantly in lacking the long, low rostral
> ramus. Its
> shape has even led some workers to suggest that it
> is from a
> sinraptorid. This all suggests that - assuming that
> _Megalosaurus bucklandii_ [whatever material you
> base it
> on] is a megalosaurid - (1) OUM J13506 is not from
> bucklandii_, nor from a megalosaurid at all and (2)
> there is
> more than one big theropod in the Stonesfield Slate
> Fm. Go
> here for my original point....
> As has been discussed at length on this list,
> Pickering maintains (following Welles) that much of
> large theropod material from Stonesfield belongs
> and truly does represent a single skeleton.
> Therefore _M.
> bucklandii_ is not based only on the dentary OUM
> but on a suite of specimens. While it is not clear
> that this is
> the case from Buckland 1824, Stephan is not alone in
> view as it was also advocated by Delair and [the
> Sarjeant (2002). According to the following post by
> Stephan, OUM J13506 is supposed to be part of this
> associated skeleton...
> Please correct me if I'm mistaken (Stephan: you
> two maxillae but do not cite specimen OUM J13506).
> OUM J13506 is supposed to be part of the allegedly
> associated _M. bucklandii_ specimen, and given that
> J13506 is fundamentally different from other
> maxillae, then either...
> (1) Buckland's original specimens do represent one
> but the maxilla shows that _M. bucklandii_ is (a)
> fundamentally different from all other megalosaurids
> or (b)
> not a megalosaurid (!).
> (2) Buckland's original specimens do not represent
> skeleton, the association of these elements with the
> OUM J13505 is incorrect and there is more than one
> theropod at Stonefield.
> Moving briefly on to something entirely different,
> Keesey wrote...
> > That's *aluminum*! :)
> Pains me to say it, but aluminum is the correct
> spelling. This was changed in British English when
> all -um
> element endings were standardised to -ium (some time
> the early 1900s I believe). American English
> preserves the older spelling and pronunciation.
> Darren Naish
> School of Earth & Environmental Sciences
> University of Portsmouth UK, PO1 3QL
> email: email@example.com
> tel: 023 92846045
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