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NEW EVENTS IN GONDWANA & UK
Just received a pile of extended abstracts from _Journal of African
Earth Sciences_, apparently there was a special volume called
'Gondwana 10: Event Stratigraphy of Gondwana_ - I don't have the full
citation: does anyone? Several of these abstracts relate to
dinosaurs and contemporary fauna. Here are the most interesting
ARCUCCI, A.B. New information about dinosaur precursors from the
Triassic Los Chanares Fauna, La Rioja, Argentina.
_Lewisuchus admixtus_ is a dinosauriform related to _Marasuchus_, and
_Pseudolagosuchus_ may be a synonym of it. The asymmetrical pes
previously referred to _L. admixtus_ 'can be identified as belonging
to a much smaller proterochampsid'. (Time to redraw that little
BAEZ, A.M. and MARSICANO, C.A. A heterodontosaurian ornithischian in
the Upper Triassic of southern Patagonia?
Heterodontosaurs are referred to in this abstract as
Heterodontosauria (=Heterodontosauridae sensu Weishampel and Witmer,
1990). A weathered left posterior maxillary fragment with dentition
was found in the Laguna Colorada Fm of the El Tranquilo Group (late
Ladinian-early Carnian) of the Santa Cruz Province and exhibits
derived characters of the _Heterodontosaurus_-_Lycorhinus_ clade. The
material is closest to _Heterodontosaurus_ in having no cingulum or
constriction separating crown from root, and in wear patterns..
'Thus, a relatively advanced heterodontosaurian, _Heterodontosaurus_
or a closely related taxon, is represented in the Upper Triassic of
southern South America'. Cool!
DE KLERK, W.J., FORSTER, C.A., ROSS. C.F., SAMPSON, S.D. and
CHINSAMY, A. A review of recent dinosaur and other vertebrate
discoveries in the Early Cretaceous Kirkwood Formation in the Algoa
Basin, Eastern Cape, South Africa.
Briefly describes a new ornithopod known from 6 individuals -
apparently all juvs - appears to be a derived iguanodont - and a new
small theropod, previously announced at SVP 1997 I think. This
theropod is pretty complete, and it's suggested that it's a basal
coelurosaur. Has anyone seen photos of this fossil? ALSO a
camarasaurid and a diplodocid: 'Diplodocids were previously unknown
from the Cretaceous of southern Africa'.
FORSTER, C.A. The continental dance: dinosaur evolution on Gondwana.
Amongst other things, Forster notes that, if Novas (1997) is right
about abelisaurids and carcharodontosaurids being close relatives,
then 'current biogeographic hypotheses involving these clades will be
SAMPSON, S.D., WITMER, L.M., FORSTER. C.A. and KRAUSE, D.W. The
evolution and biogeography of Gondwanan theropod dinosaurs: new
information from the Late Cretaceous of Madagascar.
Mentions the (then undescribed) new skull of _Majungatholus_, and
says why they call it _Majungatholus_ rather than _Majungasaurus_.
Very importantly, Sampson et al. cite Hay et al's new model of
Gondwanan fragmentation which suggests that there were
Indo-Madagascan - S. American links, via Antarctica, until late into
the Upper Cretaceous. Expect to hear more of this in the near future.
WELMAN, J. _Euskelosaurus_ and the origin of dinosaurs.
Talks about the transformation from the primitive paired arrangement
of median eustachian tubes as seen in basal archosauromorphs (but
basal archosauriform taxa are cited - _Proterosuchus_ and
_Erythrosuchus_) to the transformed crocodile-style median system
seen in prosauropods and early theropods. _Euskelosaurus_ is said to
exhibit an intermediate condition.
Last Saturday saw the Dinosaur Society conference 'British Dinosaurs
- Their Lifes and Times', held at the Lapworth Museum, University of
Birmingham. There were a number of excellent presentations concerned
with dinosaurs, obviously focusing on the British ones. Here are a
few of them...
David Norman spoke about historical aspects of Owen's work on
_Scelidosaurus_. Faced with a complete scelidosaur skeleton - a
quadrupedal, fairly graviportal dinosaur - why did Owen not take the
opportunity to point out to his colleagues that he was right in
reconstructing the other dinosaurs in the same way? Norman addressed
this very interesting and not previously remarked upon aspect of
Dr. Norman also spoke about the morphology of _Probactrosaurus_ and
how it appears to be a sister-taxon to hadrosauroids. Basal
hadrosaurs, like _Probactosaurus_, are _Iguanodon_-like in the head,
without a marked duckbill. In his abstract Dr. Norman also addressed
the taxonomy of _Probactrosaurus_ - three species have now been
proposed but not all are valid.
Angela Milner addressed current research on spinosauroids, and lots
of new/undescribed material was shown, including possible spinosaur
material from Patagonia and at least two new African taxa, one of
which is huge but very very gracile in the snout. A photo of one
spinosaur skull, whereabouts unknown, depicted a beast whose head
would perhaps have been 2.5 m long (as shown previously at SVP 1996).
_Baryonyx_ is a member of this clade, of course, and _Irritator_ and
_Angaturama_ are too. Shared features include the lower jaw profile,
S-shaped premax-max tooth row, maxillary peg that fits into a
premaxillary socket and some interesting palatal features that I
don't want to scoop.
David Martill spoke about _Neovenator_ and the new Isle of Wight
theropod. Can't remember what he said as I wasn't paying too much
attention. Steve Hutt also spoke about the new theropod, work on
which will get underway when Steve finishes his _Neovenator_ thesis.
BTW, why on earth are there rumours that _Neovenator_ might have been
venomous? (current ish of _DinoNews_). I've handled the fossils many
times and see no basis for this whatsoever.
Last night (Wednesday 21st) saw the first episode of the BBC's epic
series _The Life of Birds_, and as it dealt with bird ancestry and
fossil history, it warrant a mention.
No discussion whatsoever of the theropod-bird thing, and
unfortunately a _Chlamydosaurus_ was shown transforming into
_Archaeopteryx_. It was strongly implied that flight arose ground up,
and that feathers may have evolved as threat display devices, as in
_Chlamydosaurus_. I do appreciate that the programme makers didn't
want to go into the bird ancestry thing too much, so I see the
The computer generated _Archaeopteryx_ was a bit lame.
Next stop after the late Jurassic was the mid Eocene Messel shales,
where a few Messel taxa were mentioned or shown, and a fleshed out
_Diatryma_ was illustrated as a computer animation. Attenborough's
claim that the biggest Messel mammals were little fox-sized
protohorses was not correct, as big hyaenodontid creodonts are known
from the site. Mention was made of a gigantic bird of prey, with a 20
ft + wingspan.. I was confused: was this a reference to the
Argentinian teratorn _Argentavis_? It didn't seem to be, as it was
mentioned in the same breath as the Messel fossils. Is there some
gigantic Eocene falconiform I have missed? I hope not. Not
The programme ended with the Land of Birds, New Zealand. The idea
they were playing with was: what might the world be like had birds
'won' instead of mammals? NZ provides the answer, and there was great
footage of kiwis, takahes, wattlebirds etc. Then there were computer
generated moa - OK I suppose, but they showed exactly the same moa in
the forests, in the grasslands, and in the mountains, whereas in fact
different moa species occupied these different environments, and
these different moa looked, well... different. _Pachyornis_ and
_Dinornis_, two of the most disparate body plans in dinornithidom,
differ markedly. The book _The Life of Birds_ does mention
_Harpagornis_, so I expected a scene where we got to see one of these
mighty raptors tackle and kill its moa prey. Indeed such a scene was
enacted, but instead of doing an animation of a real _Harpagornis_,
they superimposed some sort of forest _Accipiter_ into it all. Looked
OK, but you could tell that the bird was small.. by _H. moorei_
standards, that is.
I'm off now, and will return some time in middle November. Needless
to say, I'm going away to get married. Wish me luck.