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NEW CHINIQUODONTID & SAUROPOD REVIEW
The current issue of _Palaeontology_ has two other papers
of interest not yet mentioned here. They are...
Abdala, F. and Giannini, N. P. 2002. Chiniquodontid
cynodonts: systematic and morphometric considerations.
_Palaeontology_ 45, 1151-1170.
Chiniquodontids are diagnosed by the form of the base of
the zygomatic process and expanded pterygoid flanges. An
analysis of all taxa shows that all of them form a single
growth series, though _Chiniquodon sanjuanensis_ (new
combination for _Probelosodon sanjuanensis_ Martinez &
Forster 1996) can be differentiated from _C. theotonicus_
on the basis of dentition and the shape of zygomatic
process. In contrast to recent reviews by Hopson (1991) and
Battail (1991), _Cromptodon_, _Probainognathus_,
_Thrinaxodon_, _Aleodon_ and _Cistecynodon_ are
excluded from the chiniquodontids.
Barrett, P. M., Hasegawa, Y., Manabe, M., Isaji, S. &
Matsuoka, H. 2002. Sauropod dinosaurs from the Lower
Cretaceous of eastern Asia: taxonomic and biogeographic
implications. _Palaeontology_ 45, 1197-1217.
Isolated teeth from the Kuwjima Fm (Berriasian-
Hauterivian, Japan) are referable to the Titanosauriformes
(but not to titanosaurs). The biogeographical implications of
this are discussed - and it makes a difference whether
euhelopodids are recognised as a clade or not. Other east
Asian sauropod records are examined and here are the
(1) No nemegtosaurids in Japan - the tooth referred to this
group by Tanimoto & Mizutani (1999) is from a
_Pleurocoelus_-type titanosauriform and another reported
by Barrett & Manabe (2000) is from a pterosaur.
(2) _Asiatosaurus mongoliensis_ Osborn 1924 is a nomen
dubium and should be regarded as Eusauropoda indet.
(contra Calvo 1996). _A. kwangshiensis_ Hou et al. 1975 is
also a nomen dubium.
(3) _Chiayusaurus lacustris_ Bohlin 1953 is also a nomen
dubium and an indeterminate eusauropod. _C. asianensis_
Lee et al. 1997 is a nomen dubium but a probable
(4) _Euhelopus_ Romer 1956 is clearly valid and well
supported by many autapomorphies. Barrett et al. support
monophyly of euhelopodids and argue that Upchurch's
analyses have a higher statistical rigour than Wilson and
Sereno. Their paper was obviously submitted prior to
Wilson's new ZJLS paper and when I spoke about the
problem of euhelopodid monophyly with Jeff at SVPCA he
said that he and Paul Upchurch no longer disagreed on this
issue. Seeing as Jeff's ZJLS paper still supports non-
monophyly of Euhelopodidae I take it Paul's latest analyses
are finding the same result. Mickey did show the latest
Upchurch and Barrett sauropod cladogram in one of his
emails so this will be easy to check.
(5) _Mongolosaurus haplodon_ Gilmore 1933 is also a
nomen dubium, Neosauropoda indet, and presents an array
of possible diplodocoid and titanosaur features (they do not
mention suggestions that it might be a nemegtosaurid, and
no support for George's idea that it might be an aberrant
therizinosauroid:)). Further study needed.
Incidentally Barrett et al. refer to titanosaurs as
Titanosauroidea. I'm not too keen on this term as Upchurch
originally introduced it for _Opisthocoelicaudia_ plus other
titanosaurs and, seeing as _Opisthocoelicaudia_ is now
nested well within conventional 'titanosaurids', I would
argue that the term is not useful. Then again, Upchurch did
say he introduced it to bring (Linnean-style) stability to
(6) _Phuwiangosaurus_ is deemed contentious and Barrett
et al. are not sure of its proposed affinity with
nemegtosaurids. Though they cite Curry Rogers and Forster
(2001) they seem unconvinced of the titanosaurian status of
nemegtosaurids and opt for a basal titanosaur position. This
was written before recent data by Buffetaut was presented
(7) _Ultrsaurus tabriensis_ Kim 1983 is a nomen dubium
and Sauropoda indet.
Well, there's more, but I'll be here all day if I continue.
School of Earth & Environmental Sciences
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