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A new dromaeosaurid theropod dinosaur, Kansaignathus sogdianus gen. et sp. nov., is described based on a dentary from the Yalovach Formation (Santonian) at Kansai locality in northern Fergana Valley (Tajikistan) collected by Paleontological Institute of the Academy of Sciences of the USSR in 1963–1964. Dentary has 12 tooth alveoli and not downturned anterior end. There is a chin prominence. Dorsal margin is concave and ventral margin is convex. There are two rows of vascular foramina on the labial side and irregular intermediate foramina in the anterior part of a dentary. The interdental plates are not discernable. Kansaignathus is one of the most basal members of the subfamily Velociraptorinae. It fills the gap in the fossil record of the Velociraptorinae between the Early Cretaceous Deinonychus and more derived Campanian–Maastrichtian velociraptorines of Asia and North America.

Dromaeosaurids (Theropoda: Dromaeosauridae), a group of dynamic, swift predators, have a sparse fossil record, particularly at the time of their extinction near the Cretaceous-Paleogene boundary. Here we report on a new dromaeosaurid, Dineobellator notohesperus, gen. and sp. nov., consisting of a partial skeleton from the Upper Cretaceous (Maastrichtian) of New Mexico, the first diagnostic dromaeosaurid to be recovered from the latest Cretaceous of the southern United States (southern Laramidia). The holotype includes elements of the skull, axial, and appendicular skeleton. The specimen reveals a host of morphologies that shed light on new behavioral attributes for these feathered dinosaurs. Unique features on its forelimbs suggest greater strength capabilities in flexion than the normal dromaeosaurid condition, in conjunction with a relatively tighter grip strength in the manual claws. Aspects of the caudal vertebrae suggest greater movement near the tail base, aiding in agility and predation. Phylogenetic analysis places Dineobellator within Velociraptorinae. Its phylogenetic position, along with that of other Maastrichtian taxa (Acheroraptor and Dakotaraptor), suggests dromaeosaurids were still diversifying at the end of the Cretaceous. Furthermore, its recovery as a second North American Maastrichtian velociraptorine suggests vicariance of North American velociraptorines after a dispersal event during the Campanian-Maastrichtian from Asia. Features of Dineobellator also imply that dromaeosaurids were active predators that occupied discrete ecological niches while living in the shadow of Tyrannosaurus rex, until the end of the dinosaurs’ reign.

The dromaeosaurid theropodHalszkaraptor escuillieiis characterized by several unusual features absent in other paravians, part of which has been interpreted as diagnostic of a novel lineage adapted to a semiaquatic ecology. Recently, these evolutionary and ecological interpretations have been challenged, andHalszkaraptorhas been claimed to be a transitional form between non-dromaeosaurid maniraptoriforms and other dromaeosaurids: following that reevaluation, its peculiar body plan would represent the retention of several maniraptoran plesiomorphies, lost among other dromaeosaurids, and not an adaptation to a novel ecology. This alternative scenario is here carefully investigated and tested. It is shown that most statements supporting this scenario are based on misinterpretation of anatomical traits and bibliography. Once these statements have been corrected, character state transition optimization over a well-supported phylogenetic framework indicates that the large majority of the peculiar features of theHalszkaraptorlineage are derived novelties acquired by the latter after its divergence from the last ancestor shared with eudromaeosaurs, and thus are not maniraptoriform plesiomorphies. At least seven novelties of theHalszkaraptorlineage are convergently acquired with spinosaurids, and are integrated in semiaquatic adaptations: one of these is reported here for the first time. The amount of morphological divergence of Halszkaraptorinae from the ancestral dromaeosaurid condition is comparable to those of Microraptorinae and Velociraptorinae. Among extant taxa, the sawbills (Mergini, Anseriformes) show the closest ecomorphological similarity with the peculiar body plan inferred forHalszkaraptor. The halszkaraptorinebauplanis thus confirmed as a derived amphibious specialization, and does not represent a “transitional” stage along the evolution of dromaeosaurids.

Article in press., The theropod teeth from the Berriasian (Early Cretaceous) site of Anoual (N Morocco) are described. The assemblage is important in that it comes from one of the very few dinosaur sites of this age globally and the only one for the whole of Gondwana. The theropod teeth from Anoual are morphologically diverse. Most of the material possibly belongs to the clade Dromaeosauridae, which would be an early occurrence for this taxon. The palaeogeographic position of Anoual enables it to provide data on the dispersal events that affected terrestrial faunas during Mesozoic times. A Laurasian influence is evidenced by the presence of Velociraptorinae and, on the whole, the theropod fauna from Anoual provides support for the existence of a trans-Tethyan passage allowing terrestrial faunal interchanges during Late Jurassic and/or earliest Cretaceous times. Additionally, Anoual records the existence of diminutive theropods. However, it cannot yet be determined whether the small size of the specimens is genetic or ontogenetic.

Seven theropod taxa (Tyrannosauridae indet., Ornithomimidae indet., Therizinosauroidea cf. Neimongosaurus sp., Therizinosauroidea indet., Caenagnathidae indet., Dromaeosaurinae indet., and Velociraptorinae indet.) have been identified from the Santonian Bostobe Formation, and four taxa (Tyrannosauridae indet., Ornithomimidae indet., Therizinosauroidea indet., and Dromaeosauridae indet.) are known from the underlying Turonian Zhirkindek Formation of the northeastern Aral Sea region in Kazakhstan. These theropod faunas are similar in composition to faunas from the Turonian Bissekty Formation of Uzbekistan, Santonian Yalovach Formation of Tajikistan, and TuronianeSantonian Irendabasu and Bayanshiree (upper part) formations of northern China and southern Mongolia. The therizinosauroid cf. Neimongosaurus sp., known from an isolated femur, is the only theropod taxon from Kazakhstan currently identifiable to generic level. A therizinosauroid similar to Neimongosaurus is reported here for the first time; this genus was known previously from the Irendabasu Formation of northern China. 2007 Elsevier Ltd. All rights reserved.

Velociraptorine dromaeosaurid dinosaur teeth are reported for the first time from the Wessex Formation (Early Cretaceous, Barremian) of the Isle of Wight, southern England. They represent the second record of the Dromaeosauridae in Britain and the first of this clade from strata of the British Wealden Group.

Dromaeosaurids were rare components of most Late Cretaceous terrestrial ecosystems and are poorly known from high palaeolatitudes. New dromaeosaurid material, including a frontal and associated postcranial elements, is described from a dense monodominant ceratopsid bonebed on Pipestone Creek, near the city of Grande Prairie (Unit 3, Wapiti Formation, upper Campanian), central-western Alberta, Canada. This stratigraphic interval is significant because it records a period of terrestrial deposition at a time when much of the western interior of Canada and the United States was inundated by the Bearpaw Sea. A phylogenetic analysis recovers Boreonykus certekorum, gen. et sp. nov., as a derived eudromaeosaur, possibly within Velociraptorinae. The identification of a new dromaeosaurid from the Wapiti Formation simultaneously helps fill an important gap in the record of late Campanian dromaeosaurids, bolsters support for a partly endemic fauna within the Wapiti Formation, and potentially adds to the North...