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Colour reconstructions have provided new insights into the lives of dinosaurs and other extinct animals, by predicting colouration patterns from fossilised pigment-bearing organelles called melanosomes. Although these methods have become increasingly popular, only a small number of dinosaurs have been studied using these techniques, which require exceptional preservation of fossil feathers, leaving open key questions such as whether dinosaurs changed their plumage patterns during ontogeny. Here we reconstruct the feather colouration of an approximately one-year-old individual of the Early Cretaceous dromaeosaurid theropod Wulong bohaiensis, which to our knowledge is the first unequivocal juvenile paravian for which aspects of the original colour has been predicted. Using quadratic discriminant analysis (QDA) and multinomial logistic regression (MLR) on the most comprehensive available datasets, we find strong evidence for iridescent plumage of the forelimb and hindlimb remiges and grey plumage on other portions of the body. This suggests that some juvenile paravians used shiny iridescent feathers for signalling purposes, possibly even before reaching somatic or sexual maturity, and thus we can conclude that this paravian used iridescent signalling for intraspecific communication other than sexual signalling. Finally, our results show that when analysing fossil datasets that are entirely comprised of solid and cylindrical melanosomes QDA consistently outperforms MLR, providing more accurate and higher classification probability colour predictions. [ABSTRACT FROM AUTHOR]

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 significant 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. [ABSTRACT FROM AUTHOR]

Sixteen isolated theropod teeth were discovered in two areas in the upper Middle-lower Upper Jurassic Shishugou Formation of the Xinjiang Uyghur Autonomous Region, northwest China. This sample can be divided on the basis of qualitative features and simple quantitative metrics into seven tooth morphotypes, each of which probably represents a distinct taxon. Three of the morphotypes may be attributable to theropods already known from the Shishugou Formation, namely the alvarezsauroid Haplocheirus and the basal tetanurans Monolophosaurus and Sinraptor. The other four morphotypes, however, appear to represent new taxa, taking the known theropod diversity of the Shishugou Formation from six species to at least ten. One of the new taxa is probably a dromaeosaurid. Another appears to represent a troodontid or a relative of the potentially troodontid-like Paronychodon, itself so far known only from isolated teeth. Of the remaining two taxa, one appears to be a basal tetanuran or tyrannosauroid, whereas the other either belongs to one of these same groups or represents a ceratosaur. The probable deinonychosaurian teeth in our sample are among the oldest fossils known for this clade, and highlight the diversity of coelurosaurs in the Shishugou Formation. [ABSTRACT FROM AUTHOR]

Recent discoveries of basal dromaeosaurids from the Early Cretaceous Jiufotang and Yixian formations of Liaoning, China, add significant new information about the transition from non-avian dinosaurs to avians. Here we report on a new dromaeosaurid, Tianyuraptor ostromi gen. et sp. nov., from the Early Cretaceous Yixian Formation of western Liaoning, China, based on a nearly complete skeleton. Tianyuraptor possesses several features only seen in other Liaoning dromaeosaurids, although to a less developed degree, and it also exhibits features unknown in Laurasian dromaeosaurids but present in the Gondwanan dromaeosaurids and basal avialans, thus reducing the morphological gap between these groups. Tianyuraptor possesses a comparatively small furcula and proportionally short forelimbs. This lies in stark contrast to the possible capacity for flight in the microraptorines, which have proportionally long and robust forelimbs and large furculae. The presence of such striking differences between the Early Cretaceous Jehol dromaeosaurids reveals a great diversity in morphology, locomotion and ecology early in dromaeosaurid evolution. [ABSTRACT FROM AUTHOR]

Reports on a new dromaeosaurid dinosaur, Microraptor zhaoianus gen. et sp. nov., from the Early Cretaceous Jiufotang Formation in Liaoning, China. Size and physical features of the dinosaur, which provide insight into the morphological transition to birds; Insights into the study of the paleoecology of some bird-like theropod dinosaurs.

Reports on the earliest dromaeosaurid, Sinornithosaurus millenii from Sihetun in China. Evidence of a filamentous integument; Similarity with early birds; Phylogenetic analysis indicating that among known theropods with integumentary filaments or feathers, Dromaeosauridae is the most bird-like and is more closely related to birds than is Troodontidae.

The article reports on the discovery of the flightless winged dinosaur known as the Zhenyuanlong suni in China, referencing a report in the journal "Scientific Reports," including in regard to the dinosaur's feathers, its relationship with the anatomy of a bird and the dinosaur's length.

The famous 'feathered dinosaurs' from the Early Cretaceous of Liaoning Province, northeastern China, include several dromaeosaurids, which are among the closest relatives of birds. Most of these are small-bodied taxa with long arms and broad wings comprised of vaned feathers, but a single specimen (the holotype of Tianyuraptor) belongs to a much larger individual with reduced forelimbs, which unfortunately lacks any preserved integument. We describe a new specimen of large-bodied, short-armed Liaoning dromaeosaurid, which we designate as a new genus and species, Zhenyuanlong suni. The integument is well preserved and provides the first evidence of feather morphologies and distribution in a short-armed (and probably non-volant) dromaeosaurid, indicating that these rare and aberrant taxa had large wings consisting of pennaceous feathers on the arms and long pennaceous feathers on the tail very similar to their smaller and longer-armed relatives, but potentially lacked vaned feathers on the legs. Zhenyuanlong adds yet more diversity to the Liaoning dromaeosaurid fauna, helps further reveal a distinct short-armed bauplan among dromaeosaurids, and illuminates previously-unrecognized homoplasy that complicates dromaeosaurid phylogeny and suggests that the Liaoning taxa may not have formed their own clade. [ABSTRACT FROM AUTHOR]