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A few days back Nick Gardner mentioned that the paper on _Rajasaurus_ was
officially published. That is indeed the case, as I have a copy in my hands.
It is dated August 15, 2003, and if past experiences are any indication, it may
be a little hard to get. I know that many onlist are likely to request a pdf
file, but I'm afraid that I don't have one. As far as I know, the University
of Michigan doesn't distribute pdf copies of their Contributions online, but I
could be wrong.
So, for the sake of those that might have a little trouble obtaining this
thing, I'll summarize briefly. Nick already posted the citation and abstract,
so no need to be redundant.
The holotype (Geological Survey of India, Calcutta, GSI No. 21141/1-33) is a
partial skeleton consisting of a braincase, cervical centrum, partial dorsal
vertebrae, sacrum, partial caudal vertebrae, partial scapula, partial ilia,
left proximal pubis, right femur, left distal femur, right distal tibia, right
proximal fibula, right and left metatarsal II, and right metatarsal IV. Casts
of some of these elements are also housed at the University of Michigan Museum
of Paleontology (UMPP 9085). The specimens come from Temple Hill, near
Rahioli, and the holotype is regarded as representing a single individual. The
specimen was preserved within a melange of titanosaur bones, and was excavated
from 1982-1984. The specimens were found in the Maastrichtian Lameta Formation.
Wilson et al. note that the ilia and sacrum described as _Lametasaurus_ by
Matley (1923) match the holotype of _Rajasaurus_ in their heavy construction
and strongly divergent preacetabular process, but any conclusive referral is
avoided at this time.
_Rajasaurus_ is diagnosed by a median nasofrontal prominence, with the frontals
forming only the posterior rim of the prominence; anteroposteriorly elongate
supertemporal fenestrae, with length approx. 150% transverse breadth of
frontal; and robust ilium with transversed ridge separating the brevis fossa
from the acetabulum.
A 169-character phylogenetic analysis is presented. While each character,
including its first cladistic authorship, is listed in an appendix, tree
statistics will be discussed in an upcoming paper that, barring the usual
pitfalls of review, should hopefully be published soon. Disagreeing with
Sereno (1999) and Holtz (2000), but agreeing with Carrano et al. (2002) and
some others, the new analysis finds _Ceratosaurus_ and abelisauroids sharing a
more recent common ancestry with Tetanurae than with _Coelophysis_ and kin.
Additionally, the analysis also finds an unnamed "Niger Taxon 1" as immediately
basal to Abelisauroidea, and another unnamed "Niger Taxon 2" as an abelisaurid
closely related to _Abelisaurus_, _Rajasaurus_, and _Carnotaurus_. Perhaps
most significantly, the new analysis also includes _Deltadromeus_, and finds
this form to be a noasaurid! It is placed in a trichotomy with _Noasaurus_ and
_Masiakasaurus_. However, it is best to be cautious with this placem!
at this point, as only one character unites _Masiakasaurus_ and
_Deltadromeus_: strongly reduced distal condyles of metatarsal IV. One
character, that's it. As no coelurosaurs are included in the analysis, and
Spinosauroidea and Neotetanurae are treated as OTUs, this needs to be tested
As Sereno (1998) and Padian et al. (1999) both formulated their respective
cladistic definitions based on a monophyletic Ceratosauria including
_Ceratosaurus_ and _Coelophysis_, the authors recognize that the name
Ceratosauria is periously close to falling into synonymy. Therefore, they
accept Padian et al.'s (1999) definition (all neotheropods more closely related
to _Ceratosaurus_ than to Neornithes). Neotheropoda (node-based), Tetanurae
(stem), and Ceratosauria (stem) are configured into a node-stem triplet, as is
Abelisauroidea (node), Abelisauridae (stem), and Noasauridae (stem).
Additionally, new definitions of the latter three taxa are presented:
Abelisauroidea (_Carnotaurus_, _Noasaurus_, their most common ancestor and all
descendants); Abelisauridae (all abelisauroids more closely related to
_Carnotaurus_ than to _Noasaurus); and Noasauridae (all abelisauroids more
closely related to _Noasaurus_ than _Carnotaurus_).
Let the arguments begin.
University of Chicago
Dino Land Paleontology-http://www.geocities.com/stegob
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