[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Erketu and other Asian sauropods in new AMNH Novitates
bh480@scn.org
In case this paper has not been mentioned (it's not yet
available as free down-load from AMNH site but is on
BioOne site):
Daniel T. Ksepka and Mark A. Norel, 2010.
The Illusory Evidence for Asian Brachiosauridae: New
Material of Erketu ellisoni and a Phylogenetic
Reappraisal of Basal Titanosauriformes
American Museum Novitates 3700: 1?27
Abstract
Phylogenetic relationships among the diverse Cretaceous
sauropods of East Asia have long been controversial.
Debate has centered on whether there is any evidence for
an endemic clade of Asian species (?Euhelopodidae?) and
on the placement of these taxa within the context of
higher sauropod phylogeny. While most Cretaceous sauropod
taxa from Asia are recognized as part of Somphospondyli,
recent discoveries have suggested Brachiosauridae may
have dispersed into Asia as well. We present new fossils
and analyses bearing on these issues. Additional material
of the holotype individual of Erketu ellisoni recovered
on a subsequent visit to the type locality expands the
character data available for this unique sauropod.
Associated sauropod dorsal and caudal vertebrae were
collected from the same horizon, at a location
approximately 2 km from the holotype excavation. The
dorsal vertebra exhibits synapomorphies suggesting a
representative of Titanosauria co-occurred with Erketu
ellisoni. These new specimens, as well as recent
discoveries of contemporary Asian sauropod taxa, allow a
basis for phylogenetic reappraisal of Erketu and related
taxa. Phylogenetic results support a sister group
relationship between the Asian Cretaceous sauropods
Erketu and Qiaowanlong. Although Qiaowanlong was
described as a brachiosaurid, it joins Erketu on the
somphospondylian side of the Brachiosauridae-
Somphospondyli divergence, erasing the evidence for the
dispersal of Brachiosauridae into Asia.