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Lutungutali, new dinosauriform from Middle Triassic of Zambia



From: Ben Creisler
bcreisler@gmail.com

In the new issue of JVP:


Brandon R. Peecook, Christian A. Sidor, Sterling J. Nesbitt, Roger M.
H. Smith, J. Sebastien Steyer & Kenneth D. Angielczyk (2013)
A new silesaurid from the upper Ntawere Formation of Zambia (Middle
Triassic) demonstrates the rapid diversification of Silesauridae
(Avemetatarsalia, Dinosauriformes)
Journal of Vertebrate Paleontology 33(5): 1127-1137
DOI:10.1080/02724634.2013.755991
http://www.tandfonline.com/doi/full/10.1080/02724634.2013.755991#.UidNEMa1EYE



Recent discoveries have shown that non-dinosaurian dinosauromorphs
were morphologically diverse, globally distributed, and have a
stratigraphic range extending into the Upper Triassic. Silesauridae,
the sister group to Dinosauria, contains at least seven species. Here
we describe Lutungutali sitwensis, gen. et sp. nov., the first
silesaurid from the upper portion of the Ntawere Formation of the
Luangwa Basin, Zambia. The upper Ntawere Formation has been correlated
with subzone C of the Cynognathus Assemblage Zone of the Karoo Basin
in South Africa and the Lifua Member of the Manda beds in the Ruhuhu
Basin in Tanzania, both of which are considered Anisian in age and the
latter has yielded the silesaurid Asilisaurus kongwe. The results of
our phylogenetic analysis, including a new pelvic character, allies
Lutungutali with Upper Triassic silesaurids such as Silesaurus,
Sacisaurus, and Eucoelophysis rather than with the possibly coeval
Asilisaurus. The Zambian silesaurid shares a laterally oriented brevis
fossa on the ilium and a transversely thin ischium in cross-section
with Upper Triassic forms. Silesaurids were more diverse during their
early evolution in the Anisian than previously suspected. Lutungutali
and Asilisaurus are the two oldest known members of the bird-line
archosaurs represented by body fossils. Together they show that a
subclade of bird-line archosaurs was diversifying soon after its
origin, building further support for the rapid diversification of
Archosauria in the wake of the Permo-Triassic extinction.



SUPPLEMENTAL DATA—Supplemental materials are available for this
article for free at www.tandfonline.com/UJVP