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Dinosaur Plumage Coloration and appearance provide important behavioral and evolutionary information in animals. However, for the most part, we do not know the coloration of fossil terrestrial animals. Li et al. (p. 1369 , published online 4 February) have reconstructed the appearance of a theropod dinosaur by mapping features of its well-preserved feathers and comparing them with modern samples from birds. Feather color is partly determined by melanosome density and shape, and this information is preserved in a recently discovered fossil from China. The dinosaur was gray with white limbs and had a reddish crest and a speckled face.

Salamanders are a model system for studying the rates and patterns of the evolution of new anatomical structures. Recent discoveries of abundant Late Jurassic and Early Cretaceous salamanders are helping to address these issues. Here we report the discovery of well-preserved Middle Jurassic salamanders from China, which constitutes the earliest known record of crown-group urodeles (living salamanders and their closest relatives). The new specimens are from the volcanic deposits of the Jiulongshan Formation (Bathonian), Inner Mongolia, China, and represent basal members of the Cryptobranchidae, a family that includes the endangered Asian giant salamander (Andrias) and the North American hellbender (Cryptobranchus). These fossils document a Mesozoic record of the Cryptobranchidae, predating the previous record of the group by some 100 million years. This discovery provides evidence to support the hypothesis that the divergence of the Cryptobranchidae from the Hynobiidae had taken place in Asia before the Middle Jurassic period.

With ten extant families, salamanders (urodeles) are one of the three major groups of modern amphibians (lissamphibians). Extant salamanders are often used as a model system to assess fundamental issues of developmental, morphological and biogeographical evolution. Unfortunately, our understanding of these issues has been hampered by the paucity of fossil evidence available to assess the early history of the group. Here we report the discovery of an extraordinary sample of salamander fossils, some with rare soft-tissue impressions, from the Upper Jurassic of China. With over 500 articulated specimens, this assemblage documents the morphological diversity of early urodeles and includes larvae and adults of both neotenic and metamorphosed taxa. Phylogenetic analysis confirms that these salamanders are primitive, and reveals that all basal salamander clades have Asian distributions. This is compelling evidence for an Asian origin of Recent salamanders, as well as for an extensive and early radiation of several major lineages. These discoveries show that the evolution of salamanders has involved phylogenetic and ecological diversification around a body plan that has remained fundamentally stable for over 150 million years.

Microraptor zhaoianus is known from several specimens collected in western Liaoning Province, China. However, several aspects of the morphology of Microraptor remain unknown or ambiguous due to poor preservation of the described specimens. A well-preserved new specimen of Microraptor zhaoianus is described in this study. This specimen preserves signifi¬ cant morphological details that are not present or are poorly preserved in the other Microraptor specimens including aspects of the skull, the rib cage, and the humerus. These new characters corroborate Microraptor as a member of the Dromaeosauridae as previously suggested and support the close relationship of troodontids and dromaeosaurids (Deinonychosauria). The morphology of the rib cage also suggests Microraptor and the early volant avialans very likely may have shared a similar mechanism to assist respiration.

SYNOPSIS A new, large compsognathid theropod, Huaxiagnathus orientalis gen. et sp. nov., from the Early Cretaceous Yixian Formation deposits of Liaoning Province, People's Republic of China is described. The holotype specimen is nearly complete, lacking only the distal portion of the tail. It is the second largest theropod taxon discovered from Jehol Group sediments. Like all compsognathids, Huaxiagnathus has short forelimbs and a relatively unspecialised coelurosaur body plan. Previously, fairly complete skeletons existed for only two small-bodied taxa of compsognathids, Compsognathus longipes from the Late Jurassic of Western Europe and Sinosauropteryx prima, also from the Yixian. The phylogenetic position of Huaxiagnathus orientalis was analysed using an extensive matrix of theropod characters from many taxa. Huaxiagnathus orientalis fell out at the base of the Compsognathidae, as it lacks the forelimb adaptations of more derived compsognathids. The addition of Huaxiagnathus and the two other compsognathid species to our data matrix resulted in the placement of Compsognathidae near the base of Maniraptora. Furthermore, Alvarezsauridae, Paraves, and a monophyletic Therizinosauroidea + Oviraptorosauria clade fall out in an unresolved trichotomy in the strict consensus of our most parsimonious trees.

A new ornithomimosaur from the Yixian Formation of Liaoning Province People's Republic of China is described. These beds are near the Jurassic-Cretaceous boundary. This specimen is interesting because it has several primitive characters for ornithomimosaurs such as teeth and a short first metacarpal. This taxon is placed in a phylogenetic analysis of Coelurosauria and shown to be near the base of the ornithomimosaur clade. Using this phylogeny we comment on the biogeographic history of this group.

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