Time filter

Source Type

Xing L.-D.,China University of Geosciences | Lockley M.G.,University of Colorado at Denver | Klein H.,Saurierwelt Palaontologisches Museum | Zhang J.-P.,China University of Geosciences | And 3 more authors.

A small tetrapod footprint assemblage from the Anning Formation (Upper Jurassic-Lower Cretaceous) at Konglongshan Town, Yunnan Province, China, contains possible swim traces attributable to theropod dinosaurs based on their tridactyl and mesaxonic pes morphology. Morphotypes are tentatively assigned to the ichnogenera Characichnos and Wintonopus, a third one is similar to Hatcherichnus. Due to the inherent variability observed in tetrapod swim tracks, the names are used here informally describing footprints that reflect a distinct trackmaker behavior rather than anatomically accurate images of the pes anatomy. Variation of the imprint shape is obviously due to extramorphological effects and does not indicate taxonomic diversity of trackmakers. Elongate, slender impressions associated with these tracks are discussed here as possible tail traces. Trackmakers were possibly buoyant and active swimming individuals touching and scratching the bottom of deeper waterbodies with the distal ends of their digits. The orientation of the traces perpendicular to preserved ripples suggest cross-current movement and activities. © 2015 Elsevier B.V. and Nanjing Institute of Geology and Palaeontology, CAS. Source

Xing L.-D.,China University of Geosciences | Lockley M.G.,University of Colorado at Denver | Zhang J.-P.,China University of Geosciences | Klein H.,Saurierwelt Palaontologisches Museum | And 3 more authors.

A dinosaur tracksite at Hemenkou (Shuangbai County, Yunnan Province) in the ?Middle-Upper Jurassic Shedian Formation that consists mainly of gray-purple feldspathic quartz sandstones was previously reported incorrectly as being in the Lower Cretaceous Puchanghe Formation. The previous assignment is also inconsistent with two regional geological maps. Although mostly yielding poorly preserved tracks, the site nevertheless indicates a diversity of theropod and sauropod trackmakers partly consistent with the Late Jurassic body fossils from the region. Purported ornithopod are re-evaluated here as those of theropods. The theropod tracks and trackways show distinct similarities to those of the Grallator- Eubrontes plexus and can be subdivided into three morphotypes that may reflect different pes anatomy and/or substrate conditions. Two sizes of tracks (small, large) indicate the presence of different size classes or species in this area in the Late Jurassic. Similarly, the sauropod trackways document three differently sized trackmakers (small-medium-large) showing a typical wide-gauge (Brontopodus) pattern. The track record is the first evidence of theropods in the ?Middle-Late Jurassic of central Yunnan, whereas the sauropod tracks suggest a relation to the coeval basal eusauropods known from this region by skeletal remains. © 2015 Elsevier B.V. and Nanjing Institute of Geology and Palaeontology, CAS. Source

Xing L.,China University of Geosciences | Parkinson A.H.,University of Witwatersrand | Ran H.,Guangxi Normal University | Pirrone C.A.,CONICET | And 5 more authors.
Historical Biology

We report the oldest fossil evidence of osteophagia by terrestrial invertebrates on both the Asian and African continents. Bones attributable to the Middle Jurassic dinosaur Chuanjiesaurus (Dinosauria: Sauropoda) were found with post-mortem insect modification in the Chuanjie Formation, Yunnan Province, China. The morphology of the borings closely matches the ichnogenus Cubiculum. Based on the lack of bioglyphs observed in Cubiculum ornatus, a new ichnospecies is proposed here. The new trace fossil, Cubiculum inornatus isp. nov., is interpreted to have been constructed for pupation by an unknown taxon of insect. Additionally, we report even older borings from Early Jurassic dinosaur bones of the Elliott Formation in the Karoo Basin, which represent the second oldest occurrence of insect traces in bone from continental settings. Both trace fossils sites have palaeogeographic implications for the origins and dispersal of osteophagia amongst terrestrial invertebrates during the Mesozoic. These discoveries push back the antiquity of pupation in animal bones by more than 100 million years to the Middle Jurassic, indicating that this behaviour, and osteophagy more generally, originated early in the Mesozoic, roughly comparable with the origination of insect pupation in woody substrates (Late Triassic). © 2015 Taylor & Francis. Source

Xing L.,China University of Geosciencs | Xing L.,China University of Geosciences | Lockley M.G.,CAS Institute of Vertebrate Paleontology and Paleoanthropology | You H.,University of Colorado at Denver | And 6 more authors.
Geological Bulletin of China

Dinosaur track and bone records often occur at different locations. However, a few formations show a close correspondence between bones and tracks that correspond to likely trackmakers. In this paper, the authors report sauropod tracks (Brontopodus) in very close geographic and stratigraphic proximity to the type locality of the eusauropod Tonganosaurus hei in the middle-upper parts of the Lower Jurassic Yimen Formation in Tongbao Village, Huili County, Panxi region of Sichuan Province. This Huili tracktrackmaker correlation is possibly existent, but still needs more evidence to confirm. As the first Jurassic sauropod tracks found in the Panxi region, the Tongbao Brontopodus tracks have provided evidence indicating coexistence of primitive sauropod and basal sauropodomorphs in Southwest China during Early Jurassic. © 2016, Science Press. All right reserved. Source

Xing L.,China University of Geosciences | Paulina-Carabajal A.,CONICET | Currie P.J.,University of Alberta | Xu X.,CAS Institute of Vertebrate Paleontology and Paleoanthropology | And 4 more authors.
Acta Geologica Sinica

The neuroanatomy of the mid-sized theropod Sinosaurus triassicus from the Lower Jurassic Lufeng Formation, Lufeng Basin in Yunnan Province, China was studied using X-ray computed tomography. The braincase is characterized by a large supraoccipital knob that is capped by a posterior projection of the parietal and two external foramina for the caudal middle cerebral vein, which is completely enclosed by the supraoccipital. The basicranium has well defined, short basipterygoid processes that project ventral to the basal tubera. The basisphenoid is expanded, projects posteroventrally, and is pierced by four pneumatic recesses. The endocranial morphology resembles that observed in other basal theropods - in particular some allosauroids - and has a strongly marked pontine flexure and a large dorsal expansion. The inner ear morphology is also similar to that observed in other basal theropods, with slender semicircular canals. The anterior semicircular canal is 20% larger than the posterior semicircular canal, and the angle formed between them is less than 90° when seen in dorsal view. © 2014 Geological Society of China. Source

Discover hidden collaborations