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new ref: Mazzetta et al, 2004


Gerardo V. Mazzetta, Per Christiansen , Richard A. Fariña. 2004. Giants and 
Bizarres: Body Size of Some Southern South American Cretaceous Dinosaurs. 
Historical Biology: A Journal of Paleobiology . Published Online O2 july, 2004.

Body masses of some South American dinosaurs are estimated. The sauropod 
Argentinosaurus huinculensis reached 73 tonnes, and therefore, is the largest 
of all land animals whose mass has been rigorously obtained. Another sauropod, 
Antarctosaurus giganteus, was the second largest, at nearly 69 tonnes, while 
Antarctosaurus wichmannianus reached 34 tonnes. A third sauropod, the 
bizarre-looking Amargasaurus cazaui, was much smaller, with a body mass of only 
2.5 tonnes. Among theropods, the body mass of the strangely looking, horned 
Carnotaurus sastrei, was volumetrically estimated at 1.5 tonnes, while 
allometric equations on limb measurements yielded overestimations. Moreover, 
the holotype specimen of Giganotosaurus carolinii (MUCPv-CH-1) was about as 
large as the average-sized Tyrannosaurus rex, and only marginally smaller than 
"Sue", the largest specimen. However, a new dentary of Giganotosaurus 
(MUCPv-95) is 8% longer than that of the holotype. Assuming geometric 
similarity, t!
hat individual must have had a body mass above 8 tonnes and hence must have 
been the largest theropod ever found.


Also in this adress is the abstract of the Mirischia paper:

Darren Naish, David M. Martill, Eberhard Frey. 2004. Ecology, Systematics and 
Biogeographical Relationships of Dinosaurs, Including a New Theropod, from the 
Santana Formation (?Albian, Early Cretaceous) of Brazil. Historical Biology: A 
Journal of Paleobiology . Published Online O2 july, 2004.

Although rare, dinosaurs are well preserved in calcareous nodules of the 
Santana Formation (Early Cretaceous, ?Albian) of the Araripe Basin, in 
northeastern Brazil. So far, including only a spinosauroid and three 
coelurosaurs, the dinosaur fauna appears depauperate. High theropod diversity 
in assemblages where other dinosaurs are rare or absent is not unique to the 
Santana Formation. It is seen also in several other assemblages, including 
Solnhofen and the Maevarano Formation of Madagascar. We consider several 
factors, including the occurrence of intraguild predation, the possibility that 
small theropods could subsist in marginal environments, and reliance on coastal 
resources, that may have been responsible for this apparent ecological 
imbalance. A new coelurosaur from the Santana Formation, here formally named 
Mirischia asymmetrica, is shown to be distinct from Santanaraptor placidus 
[Kellner, A.W.A. (1999) "Short note on a new dinosaur (Theropoda, 
Coelurosauria) from the !
Santana Formation (Romualdo Member, Albian) northeastern Brazil", Boletim do 
Museu Nacional, Nova Serie, Rio de Janeiro, Brasil 49, 1-8]. Other theropods 
from the Santana Formation are briefly reviewed. Mirischia is a compsognathid, 
more similar to the European Compsognathus than to the Asian Sinosauropteryx.