A probable tyrannosaurid track from the Upper Cretaceous of southern China

A large number of Upper Cretaceous(Maastrichtian)dinosaur skeletal fossils have been found in the Nanxiong Basin and adjacent Ganzhou area,including those of theropods,sauropods and hadrosaurids.However,known dinosaur ichnoassemblages from the Nanxiong Basin partly indicate a different fauna,with dominating large-and medium-sized ornithopods,theropods,and pterosaurs(1,2)This is one of many known examples where trace and body fossil assemblages from the same formation or geologically discrete region show a different composition.Palecological and paleobiogeographical analyses therefore should consider data from both,before any conclusions can be drawn.Formations can be classified according to the relative degree of similarity or congruity(or difference/incongruity)between trace and body fossils into the 5 categories proposed by Lockley[3].

Late Triassic sauropodomorph and Middle Jurassic theropod tracks from the Xichang Basin,Sichuan Province,southwestern China:First report of the ichnogenus Carmelopodus

Upper Triassic and Middle Jurassic strata of the Xichang Basin in Sichuan Province, southwestern China, yielded important dinosaur ichnofossils. From the Xujiahe Formation of the Yiguojiao tracksite, we report a Late Triassic footprint assemblage in China and the first discovery of diagnostic Triassic sauropodomorph tracks in this region. The tracks share a number of features in common with the ichnogenera Eosauropus(Late Triassic) and Liujianpus(Early Jurassic). The neighboring Bingtu tracksite is stratigraphically younger(Shaximiao Formation, Middle Jurassic) and preserves small tridactyl theropod tracks that represent the first occurrence of the ichnotaxon Carmelopodus in China and Asia. While these tracks are morphologically comparable to those from the Middle Jurassic type locality in North America, the specimens from China show the proximal margin of the digit IV impression in a more cranial position, which may indicate a trackmaker with a relatively short metatarsal IV. In addition to the skeletal record, the Carmelopodus footprints document the presence of small theropods in the dinosaur fauna of the Middle Jurassic Shaximiao Formation.

The first theropod tracks from the Middle Jurassic of Gansu,Northwest China:new and rare evidence of quadrupedal progression in theropod dinosaurs

A new Middle Jurassic tracksite dominated by non-avian theropod footprints from the Wangjiashan Formation in Pingchuan District,Baojishan Basin,Gansu Province has yielded a unique trackway with four consecutive manus-pes sets.Only three previous examples,all Early Jurassic in age,of theropod trackways are known with convincing examples of manus tracks and in each case,only two tracks were recorded in association with pes tracks with metatarsal impressions and pelvic traces indicating crouching behavior.Thus,this is the first example of manus tracks registered while a theropod trackmaker was walking.This unique configuration is here designated as Grallator pingchuanensis ichnosp.nov.which shows the trackmaker forelimbs registering in a wide straddle gait,much wider than the pes trackway width.G.pingchuanensis confirms previous reports that theropods could occasionally register tridactyl,ectaxonic manus traces.In the case of the Pingchuan trackway,the short step indicates an animal moving at a slow speed,probably due to a soft substrate.

Lower Cretaceous sauropod trackways from Lishui City and an overview of dinosaur dominated track assemblages from Zhejiang Province, China

A relatively small number of tetrapod tracksites from Zhejiang Province fills out the fossil record from that region,which is also known to have yielded both saurischian（titanosauriform, coelurosaur） and ornithischian（basal ornithopod, ankylosaurian） body fossils as well as dinosaurian eggs. We use photogrammetry and 3 D imaging to reinterpret the sauropod tracks from Lishui City, which revealed the existence of trackways. The track record from three documented sites in Zhejiang Province includes avian and non-avian theropod, sauropod, ornithopod and pterosaur tracks. Previous work showed that the purported new bird ichnospecies Dongyangornipes sinensis is a synonym of Uhangrichnus chuni, while we here consider Pteraichnus dongyangensis as a nomen dubium. Such ＂provincial ichnotaxonomy＂ may mask similarities in the ichnofauna across large regions. In fact, we show that the ichnofauna is similar to that found in the Early Cretaceous elsewhere in China.

The new ichnotaxon Eubrontes nobitai ichnosp. nov. and other saurischian tracks from the Lower Cretaceous of Sichuan Province and a review of Chinese Eubrontes-type tracks

The Jiaguan Formation and the underlying Feitianshan Formation(Lower Cretaceous) in Sichuan Province yield multiple saurischian(theropod–sauropod) dominated ichnofaunas. To date, a moderate diversity of six theropod ichnogenera has been reported, but none of these have been identified at the ichnospecies level. Thus, many morphotypes have common "generic" labels such as Grallator, Eubrontes, cf. Eubrontes or even "EubrontesMegalosauripus" morphotype. These morphotypes are generally more typical of the Jurassic, whereas other more distinctive theropod tracks(Minisauripus and Velociraptorichnus) are restricted to the Cretaceous. The new ichnospecies Eubrontes nobitai ichnosp nov. is distinguished from Jurassic morphotypes based on a very wellpreserved trackway and represents the first-named Eubrontes ichnospecies from the Cretaceous of Asia.