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Jurassic avialan dinosaur from China

New dinosaur or bird from China...in Nature today

A Jurassic avialan dinosaur from China resolves the
early phylogenetic history of birds

Pascal Godefroit1, Andrea Cau2, Hu Dong-Yu3,4, François Escuillie´5, Wu
Wenhao6 & Gareth Dyke7

The recent discovery of small paravian theropod dinosaurs with
well-preserved feathers in the Middle­Late Jurassic Tiaojishan
Formation of Liaoning Province (northeastern China)1­4 has challenged
the pivotal position of Archaeopteryx3,4, regarded from its
discovery to be the most basal bird. Removing Archaeopteryx
from the base of Avialae to nest within Deinonychosauria implies
that typical bird flight, powered by the forelimbs only, either
evolved at least twice, or was subsequently lost or modified in some
deinonychosaurians3,5. Here we describe the complete skeleton
of a new paravian from the Tiaojishan Formation of Liaoning
Province, China. Including this new taxon in a comprehensive
phylogenetic analysis for basal Paraves does the following: (1) it
recovers it as the basal-most avialan; (2) it confirms the avialan
status of Archaeopteryx; (3) it places Troodontidae as the sistergroup
to Avialae; (4) it supports a single origin of powered flight
within Paraves; and (5) it implies that the early diversification of
Paraves and Avialae took place in the Middle­Late Jurassic period.

On 5/28/13 9:41 PM, "Ben Creisler" <bcreisler@gmail.com> wrote:

> From: Ben Creisler
> bcreisler@gmail.com
> A recent paper not yet mentioned on the DML:
> Dean R. Lomax and William R. Wahl   (2013)
> A new specimen of the elasmosaurid plesiosaur Zarafasaura oceanis from
> the Upper Cretaceous (Maastrichtian) of Morocco.
> Paludicola 9(2): 97-109
> http://vortex.weather.brockport.edu/~jmassare/rivp/contents.htm
> pdf:
> http://www.academia.edu/3509227/A_NEW_SPECIMEN_OF_THE_ELASMOSAURID_PLESIOSAUR_
> A new specimen of the Moroccan elasmosaurid plesiosaur Zarafasaura
> oceanis from the Maastrichtian (Upper Cretaceous) phosphate deposits
> of Morocco is described. A partial skeleton with an associated skull
> is mounted ondisplay at the Wyoming Dinosaur Center, USA. The short
> preorbital region of the skullandcontact of the squamosal with the
> parietals, jugal and postorbital, allow for identification to the
> genus. However, large amounts of  the skull and mounted skeleton are
> reconstructed so description is difficult in all but a cursory way. In
> recent years,the popularity of Moroccan material among collectors and
> the general public has increased the numberof display specimens in
> museums across the world. As plesiosaurs remain very scarce in these
> rich marine vertebrate strata, any information expanding our
> understanding of the osteology of a known species warrants study. The
> new specimen of  Zarafasaura provides information on postcranial
> elements which were previously unknown, along with additional
> information regarding a fairly complete skull that preserves elements
> that are missing in the holotype specimen.