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Spoke too soon: new theropods and new hadrosauroid from Asia in Proceedings B



Just sent a message, and then checked out the Proc B website, and found:

http://rspb.royalsocietypublishing.org/content/early/2009/04/17/rspb.2009.02
49.full
A longirostrine tyrannosauroid from the Early Cretaceous of China

   1. Daqing Li1,
   2. Mark A. Norell2,
   3. Ke-Qin Gao3,
   4. Nathan D. Smith4,5 and
   5. Peter J. Makovicky4,*

Abstract

The fossil record of tyrannosauroid theropods is marked by a substantial
temporal and morphological gap between small-bodied, Barremian taxa, and
extremely large-bodied taxa from the latest Cretaceous. Here we describe a
new tyrannosauroid, Xiongguanlong baimoensis n. gen. et sp., from the
Aptian-Albian Xinminpu Group of western China that represents a
phylogenetic, morphological, and temporal link between these disjunct
portions of tyrannosauroid evolutionary history. Xiongguanlong is recovered
in our phylogenetic analysis as the sister taxon to Tyrannosauridae plus
Appalachiosaurus, and marks the appearance of several tyrannosaurid hallmark
features, including a sharp parietal sagittal crest, a boxy basicranium, a
quadratojugal with a flaring dorsal process and a flexed caudal edge,
premaxillary teeth bearing a median lingual ridge, and an expanded axial
neural spine surmounted by distinct processes at its corners. Xiongguanlong
is characterized by a narrow and elongate muzzle resembling that of
Alioramus. The slender, unornamented nasals of Xiongguanlong are
inconsistent with recent hypotheses of correlated progression in
tyrannosauroid feeding mechanics, and suggest more complex patterns of
character evolution in the integration of feeding adaptations in
tyrannosaurids. Body mass estimates for the full-grown holotype specimen of
Xiongguanlong fall between those of Late Cretaceous tyrannosaurids and
Barremian tyrannosauroids, suggesting that the trend of increasing body size
observed in North American Late Cretaceous Tyrannosauridae may extend
through the Cretaceous history of Tyrannosauroidea though further
phylogenetic work is required to corroborate this.

http://rspb.royalsocietypublishing.org/content/early/2009/04/20/rspb.2009.02
36.full
A giant ornithomimosaur from the Early Cretaceous of China

   1. Peter J. Makovicky1,*,
   2. Daqing Li2,
   3. Ke-Qin Gao3,
   4. Matthew Lewin4,
   5. Gregory M. Erickson5 and
   6. Mark A. Norell6

Abstract

Ornithomimosaurs (ostrich-mimic dinosaurs) are a common element of some
Cretaceous dinosaur assemblages of Asia and North America. Here, we describe
a new species of ornithomimosaur, Beishanlong grandis, from an associated,
partial postcranial skeleton from the Aptian-Albian Xinminpu Group of
northern Gansu, China. Beishanlong is similar to another Aptian-Albian
ornithomimosaur, Harpymimus, with which it shares a phylogenetic position as
more derived than the Barremian Shenzhousaurus and as sister to a Late
Cretaceous clade composed of Garudimimus and the Ornithomimidae. Beishanlong
is one of the largest definitive ornithomimosaurs yet described, though
histological analysis shows that the holotype individual was still growing
at its death. Together with the co-eval and sympatric therizinosaur
Suzhousaurus and the oviraptorosaur Gigantraptor, Beishanlong provides
evidence for the parallel evolution of gigantism in separate lineages of
beaked and possibly herbivorous coelurosaurs within a short time span in
Central Asia.


And one I hadn't known was coming:

http://rspb.royalsocietypublishing.org/content/early/2009/04/17/rspb.2009.02
29.full
A new basal hadrosauroid dinosaur from the Late Cretaceous of Uzbekistan and
the early radiation of duck-billed dinosaurs

   1. Hans-Dieter Sues1,* and
   2. Alexander Averianov2


Abstract

Levnesovia transoxiana gen. et sp. nov., from the Late Cretaceous
(Middle-Late Turonian) of Uzbekistan, is the oldest well-documented taxon
referable to Hadrosauroidea sensu Godefroit et al. It differs from a
somewhat younger and closely related Bactrosaurus from Inner Mongolia
(China) by a tall sagittal crest on the parietals and the absence of
club-shaped dorsal neural spines in adult specimens. Levnesovia,
Bactrosaurus and possibly Gilmoreosaurus represent the earliest radiation of
Hadrosauroidea, which took place during the Cenomanian-Turonian and possibly
in North America. The second, Santonian-age radiation of Hadrosauroidea
included Aralosaurus, Hadrosauridae and lineages leading to Tanius
(Campanian) and Telmatosaurus (Maastrichtian). Hadrosauridae appears to be
monophyletic, but Hadrosaurinae and Lambeosaurinae originated in North
America and Asia, respectively.

Thomas R. Holtz, Jr.
Email: tholtz@umd.edu   Phone: 301-405-4084
Office: Centreville 1216                        
Senior Lecturer, Vertebrate Paleontology
Dept. of Geology, University of Maryland
http://www.geol.umd.edu/~tholtz/
Fax: 301-314-9661               

Faculty Director, Earth, Life & Time Program, College Park Scholars
http://www.geol.umd.edu/~jmerck/eltsite/
Faculty Director, Science & Global Change Program, College Park Scholars
http://www.geol.umd.edu/sgc
Fax: 301-405-0796

Mailing Address:        Thomas R. Holtz, Jr.
                        Department of Geology
                        Building 237, Room 1117
                        University of Maryland
                        College Park, MD 20742 USA