A new dromaeosaurid (Dinosauria: Theropoda) from the Upper Cretaceous Wulansuhai Formation of Inner Mongolia, China

We describe a new dromaeosaurid theropod from the Upper Cretaceous Wulansuhai Formation of Bayan Mandahu, Inner Mongolia. The new taxon, Linheraptor exquisitus gen. et sp. nov., is based on an exceptionally well-preserved, nearly complete skeleton. This specimen represents the fifth dromaeosaurid taxon recovered from the Upper Cretaceous Djadokhta Formation and its laterally equivalent strata, which include the Wulansuhai Formation, and adds to the known diversity of Late Cretaceous dromaeosaurids. Linheraptor exquisitus closely resembles the recently reported Tsaagan mangas. Uniquely among dromaeosaurids, the two taxa share a large, anteriorly located maxillary fenestra and a contact between the jugal and the squamosal that excludes the postorbital from the infratemporal fenestra. These features suggest a sister-taxon relationship between L. exquisitus and T. mangas, which indicates the presence of a unique dromaeosaurid lineage in the Late Cretaceous of Asia. A number of cranial and dental features seen in L. exquisitus and T. mangas, and particularly some postcranial features of L. exquisitus, suggest that these two taxa are probably intermediate in systematic position between known basal and derived dromaeosaurids. The discovery of Linheraptor exquisitus is thus important for understanding the evolution of some salient features seen in the derived dromaeosaurids

First Lower Jurassic vertebrate burrow from southern Africa (upper Elliot Formation, Karoo Basin, South Africa)

Vertebrate burrows are common ichnofossils in the Permo-Triassic of the main Karoo Basin in South Africa. They are generally attributable to one of several lineages of therapsid, including the derived clade known as cynodonts. Despite the presence of cynodont species in the Upper Triassic and Lower Jurassic of the Karoo Supergroup, vertebrate burrows have never been reported from this part of the succession. Recent fieldwork recovered a semi-elliptical burrow cast in the Lower Jurassic upper Elliot Formation (Stormberg Group) on the farm Edelweiss 698 (Free State). The horizontal and vertical diameters of the burrow cast are ~ 18 and ~ 7 cm, respectively. This semi-horizontal, straight to slightly sinuous tunnel is ~ 50 cm long with a ramp angle of  20 cm deep) desiccation cracks, invertebrate trace fossils, calcareous rhizoconcretions, and spherical-to-elongated carbonate nodules. These and other associated sedimentary features provide evidence for a semi-arid, fluvio-lacustrine palaeoenvironment during the burrowing activity. Based on comparisons to fossil and modern burrows, this burrow cast is interpreted as a vertebrate burrow, and is the first record of vertebrate fossorial activity within the Lower Jurassic of southern Africa. The ancient burrow architect has yet to be positively identified. However, given the size and morphology of the burrow and the occurrence of similar sized fossil cynodont therapsids that inhabited the main Karoo Basin in the earliest Jurassic, the potential burrow-maker may be tentatively linked to the Cynodontia (e.g., Pachygenelus - an advanced tritheledontid).Fil: Bordy, E.M.. University Of Cape Town;Fil: Sciscio, L.. University Of Cape Town;Fil: Abdala, Nestor Fernando. University of the Witwatersrand; Sudáfrica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: McPhee, B.W.. University of the Witwatersrand; SudáfricaFil: Choiniere, J.N.. University of the Witwatersrand; Sudáfric