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Xing L.,China University of Geosciences | Lockley M.G.,University of Colorado at Denver | Marty D.,Naturhistorisches Museum Basel | Pinuela L.,Museo del Jurasico de Asturias MUJA Jurassic Museum of Asturias | And 3 more authors.
Cretaceous Research | Year: 2015

A re-description of the Early Cretaceous Zhaojue dinosaur tracksite (Sichuan Province, China) is the major focus of the present work. The tracksite is located in an active copper mine, and a dinosaur track-bearing surface of about 1500m2 (named tracksite I) initially discovered in 1991, has since almost completely collapsed due to ongoing quarry activities. Only about 5% of the initial surface still remains in place (named "remaining tracksite"), while due to the collapse a few new but rather poorly-preserved tracks were unearthed on an underlying level. While the tracks still in place were studied using common field techniques, a schematic tracksite map of the collapsed surface was drawn based on a "corrected orthophotograph" that was generated from overview photographs and from video frames. Fortunately, the resolution of some of the close-up video frames is sufficiently high to observe general track morphology, and to re-interpret previously wrongly identified trackways. Here, we report a quite diverse ichnocoenosis consisting of sauropod, ornithopod, theropod, and pterosaur trackways and isolated tracks. The sauropod trackways belong to the Brontopodus-type and were possibly left by medium-sized titanosaurs. One of the sauropod trackways turns around and makes an astonishingly narrow turn of more than 180° with very pronounced "off-tracking" of the manus with respect to the pes. Such unusual trackways are important for the reconstruction of sauropod locomotion. The theropod trackways were left by small and medium-sized animals with the imprint morphology being similar to that of the ichnogenera Grallator and Eubrontes. Large tridactyl tracks with blunt toes are tentatively identified as ornithopod tracks and may be described as Caririchnium-type tracks. Pterosaur tracks can be assigned to Pteraichnus. The association of pterosaur with small theropod tracks is rather unusual, and this tracksite further corroborates the frequent presence of large ornithopods in inland environmental settings. © 2014 Elsevier Ltd. Source

Xing L.,China University of Geosciences | Lockley M.G.,University of Colorado at Denver | Marty D.,Office de la culture | Klein H.,Saurierwelt Palaontologisches Museum | And 7 more authors.
Cretaceous Research | Year: 2013

New dinosaur track assemblages were discovered recently in the Tianjialou Formation of the Lower Cretaceous Dasheng Group in Shandong Province, China. Theropods are represented by the trackways of two different medium-sized groups: (1) tridactyl tracks with a typical mesaxonic shape; (2) functionally didactyl tracks attributed to deinonychosaurian theropods. The latter report, the third from the Cretaceous of Shandong Province, enlarges the global record of didactyl theropod tracks, until now sparsely documented from only a few locations in Asia, North America and Europe. A number of features in the dromaeosaur trackway suggest the assignment to cf. Dromaeosauripus. Several medium-sized trackways resemble the narrow-gauge, small manus ichnogenus Parabrontopodus, and one large trackway is characterised by a wide-gauge and large manus, similar to Brontopodus. This suggests the co-occurrence of two different sauropod groups. A further component in these ichnoassemblages is a tetradactyl morphotype and trackways of ornithischian affinity that are tentatively attributed to psittacosaurs. © 2013 Elsevier Ltd. Source

Xing L.D.,China University of Geosciences | Lockley M.G.,University of Colorado at Denver | Klein H.,Saurierwelt Palaontologisches Museum | Gierlinski G.D.,JuraPark | And 5 more authors.
Palaeoworld | Year: 2014

Deposits from the Ordos Basin of mid-western China are rich in body fossils and ichnofossils of Early Cretaceous vertebrates. Thousands of Early Cretaceous sauropod, theropod and bird tracks described since 1958 have been found at several localities in the basin. We report two new sites (Dijiaping and Bawangzhuang) in the Luohe Formation of the Ordos Basin, Shaanxi Province, which contain small theropod footprints that are here referred to the ichnogenus Jialingpus. The assignment is based on pad configurations including (1) the large metatarsophalangeal area positioned in line with the axis of digit III, (2) the subdivision of this part into a small pad behind digit II, which in some specimens is close to the general position of the hallux (digit I), and a large metatarsophalangeal pad behind digit IV, and (3) a distinct inter-pad space between metatarsophalangeal pads and proximal phalangeal pads of digits II and III. We re-describe the type material of the type ichnospecies Jialingpus yuechiensis from the Upper Jurassic Penglaizhen Formation of Sichuan Province, proposing a largely amended diagnosis for this ichnotaxon. The presence of a digit I trace in the holotype, indicating a relatively long hallux, and the large metatarsophalangeal area positioned in line with digit III distinguishes Jialingpus from the ichnogenus Grallator and similar tracks that all lack these features. The only difference between Jialingpus specimens from the Cretaceous of the Ordos Basin and those of the Jurassic Penglaizhen Formation is the larger digit divarication in the Cretaceous taxon. This is the fourth record of Jialingpus in China and the second in Cretaceous strata, with the first being those from the Huangyangquan locality in Xinjiang, China. © 2014 Elsevier B.V. and Nanjing Institute of Geology and Palaeontology, CAS. Source

Farlow J.O.,Indiana University | Schachner E.R.,University of Utah | Sarrazin J.C.,University of Utah | Klein H.,Saurierwelt Palaontologisches Museum | Currie P.J.,University of Alberta
Anatomical Record | Year: 2014

The crocodile-line basal suchian Poposaurus gracilis had body proportions suggesting that it was an erect, bipedal form like many dinosaurs, prompting questions of whether its pedal proportions, and the shape of its footprint, would likewise "mimic" those of bipedal dinosaurs. We addressed these questions through a comparison of phalangeal, digital, and metatarsal proportions of Poposaurus with those of extinct and extant crocodile-line archosaurs, obligate or facultatively bipedal non-avian dinosaurs, and ground birds of several clades, as well as a comparison of the footprint reconstructed from the foot skeleton of Poposaurus with known early Mesozoic archosaurian ichnotaxa. Bivariate and multivariate analyses of phalangeal and digital dimensions showed numerous instances of convergence in pedal morphology among disparate archosaurian clades. Overall, the foot of Poposaurus is indeed more like that of bipedal dinosaurs than other archosaur groups, but is not exactly like the foot of any particular bipedal dinosaur clade. Poposaurus likely had a digitigrade stance, and its footprint shape could have resembled grallatorid ichnotaxa, unless digit I of the foot of Poposaurus commonly left an impression. Anat Rec, 297:1022-1046, 2014. © 2014 Wiley Periodicals, Inc. Source

Xing L.,China University of Geosciences | Lockley M.G.,University of Colorado at Denver | Zhang J.,China University of Geosciences | Klein H.,Saurierwelt Palaontologisches Museum | And 2 more authors.
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2014

Copper mining activities in a huge quarry in the fluvial-lacustrine Lower Cretaceous Feitianshan Formation near Zhaojue, Sichuan Province have temporarily exposed large track-bearing surfaces that require rapid documentation before they are subject to erosion or damage from collapse or destruction by mining. Due to the urgent need to document these sites several preliminary studies of representative material have been completed, and more than 1000 tracks have been observed. Here we present maps of two large surfaces, with a combined area of ~1000m2, representing the same stratigraphic level, and yielding multiple trackways of measurable quality, including at least 8 theropod, 7 sauropod, and 22 ornithopod trackways. Additional trackmakers of the two latter groups are also well-represented by natural casts derived from an overlying unit disturbed by quarrying. The sauropod tracks are assigned to the ubiquitous ichnogenus Brontopodus. The ornithopod tracks belong to the ichnogenera Caririchnium, attributed to quadrupeds or facultative bipeds, and Ornithopodichnus, corresponding to smaller bipeds. Based on size and morphology the theropod trackways appear to represent diverse morphotypes, including one attributed to the new ichnospecies Siamopodus xui. The Feitianshan Formation ichnofauna, which also includes pterosaur tracks from other nearby surfaces, is moderately diverse and indicates an abundant presence of archosaurs in the region during the Early Cretaceous. © 2014 Elsevier B.V. Source

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