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The aim of the present contribution is to describe the first ornithischian species from the Huincul Formation (Cenomanian-Turonian, Upper Cretaceous) at the Pueblo Blanco Natural Reserve, Río Negro province, Argentina. The new species, named Chakisaurus nekul gen. et sp. nov., can be comfortably included among elasmarian ornithopods. The new species shows humeral anatomy that is congruent with smaller members of the clade (e.g. Anabisetia, Notohypsilophodon), and differs from larger taxa (e.g. Talenkauen, Mahuidacursor) which show humeral features probably related with graviportal habits, such as lack of shaft torsion and a distally located deltopectoral crest. This indicates that graviportal habits were probably acquired independently in elasmarians from other large-sized taxa, such as hadrosauroids. Caudal vertebrae of the new species also show a unique combination of characters shared with other elasmarians, which are absent in previously known ornithopods. These features indicate that some elasmarians had a protonic tail posture, which is unknown in other ornithischians and was previously considered unique to derived titanosaurian sauropods. The shape of transverse processes and neural spines of caudal vertebrae indicate that at least some elasmarians had improved cursorial habilities, that were convergently acquired by selected theropod clades. [ABSTRACT FROM AUTHOR]

Post-Wealden dinosaur remains are rare in the UK, so any material from late Early or Late Cretaceous deposits is potentially of palaeoecological and palaeobiogeographical significance. Four dinosaur specimens collected from the Woburn Sands Formation (Aptian) of Upware, Cambridgeshire were described briefly by Walter Keeping in 1883, but have not been reappraised since. These specimens are identified herein as a ?turiasaurian sauropod tooth and indeterminate iguanodontian ornithopod remains (a tooth, middle caudal vertebra, pollex ungual). Although collected from the Woburn Sands Formation, it is likely that all of these fossils were reworked from older (now absent) sediments and they have usually been regarded as either 'Wealden' or Neocomian in age, presumably due to previous identifications of some of these specimens as Iguanodon. However, consideration of UK dinosaur faunas and regional geology indicates that these fossils could potentially be older. Further work is needed on the derived terrestrial fossils of the Lower Greensand Group in order to constrain their ages more precisely so that they can be incorporated into broader studies of regional diversity and palaeoecology. [ABSTRACT FROM AUTHOR]

Abstract The fossiliferous site of La Cantalera-1 (Teruel, Spain) has to date provided remains of more than 30 vertebrate taxa, including dinosaurs, crocodyliforms, pterosaurs, mammals, lizards, turtles, lissamphibians and teleosteans. Located in the lower part of the Blesa Formation (lower Barremian), it is one of the richest vertebrate-bearing deposits from the Lower Cretaceous of the Iberian Peninsula. In this work, taphonomic and palaeohistological studies are carried out on the basis of ornithischian (Ornithopoda and Ankylosauria) dinosaur samples in order to assess the diagenetic processes, to characterize the histological microstructures and, if possible, to make palaeobiological inferences about the state of maturation of the individuals. A variety of techniques are used in the taphonomic study, including scanning electron microscopy (SEM), cathodoluminescence (CL), X-ray diffraction (XRD) and ultraviolet fluorescence (UVF). The bone of the dinosaur samples has been converted into francolite (fluorapatite carbonate); the trabecular cavities are filled with semi-spherical forms of goethite and two different phases of calcite. In addition, the SEM and UVF techniques suggest the activity of coccoid-form bacteria and filaments of bacterial origin (biofilms?) in the bones, which possibly favoured fossilization. The dinosaur remains were subjected to fossil-diagenetic processes in a phreatic environment after a rapid burial, without appreciable seasonality effects. On the other hand, the palaeohistological study of both skeletal and dermal bones found in La Cantalera-1 shows a community of herbivorous dinosaurs composed mostly of immature ornithopods and at least one Polacanthus -like ankylosaur, as suggested by the organizational pattern of structural collagen fibres seen in some samples. The palaeobiological inferences drawn from this study support previous interpretations of a relative abundance of immature ornithischians in La Cantalera-1. Highlights • First palaeohistological study of Ornithischia from La Cantalera-1 (Spain). • Presence of Polacanthus -like ankylosaur suggested by histological features of osteoderms. • Mineral fill suggests the dinosaur bones underwent rapid burial in a phreatic environment. • Evidence of microbial (nanobacterial) participation, possibly favouring fossilization. [ABSTRACT FROM AUTHOR]

Abstract A new ornithopod dinosaur, the medium-sized Sektensaurus sanjuanboscoi gen. et sp nov. from the Coniacian–Maastricthian strata of the Lago Colhué Huapi Formation, Golfo San Jorge Basin, Patagonia, is here described. The specimen consists of disarticulated postcranial bones belonging to a single individual. It is diagnosed by an unique association of five autapomorphies on the dorsal and sacral vertebrae and the humerus. A cladistics analysis indicates that Sektensaurus was an iguanodontian ornithopod which inhabited Patagonia during the Late Cretaceous. Likewise, Sektensaurus is the first non-hadrosaurid, probably elasmarian, ornithopod recorded from the uppermost Cretaceous of central Patagonia. In a broad context, this discovery increases the anatomical knowledge of ornithopods and adds new data on the composition of dinosaur faunas that lived in Patagonia close to the Antarctica, at the end of the Cretaceous. [ABSTRACT FROM AUTHOR]

The Lower Cretaceous Wessex Formation of the Isle of Wight, UK, has produced a diverse dinosaurian fauna over the past 150 years. Hypsilophodontids are the most common small dinosaurs in the assemblage. Currently all hypsilophodontids are referred to Hypsilophodon foxii , originally described based on skulls and skeletons from the Hypsilophodon bed near Cowleaze Chine, in the uppermost Wessex Formation. We report a new hypsilophodontid, Vectidromeus insularis gen. et sp. nov., from exposures near Sudmoor Point, lying at the base of the exposed Wessex, ∼150 m below the Hypsilophodon beds. Associated elements of the dorsal vertebrae, pelvis, hindlimbs, and tail are preserved. The specimen represents a juvenile, but differs from adult and juvenile Hypsilophodon foxii in the short and deep posterior iliac blade, short pubic peduncle, laterally exposed brevis fossa, rectangular ischia, and large fourth trochanter. Vectidromeus adds to the diversity of dinosaurs in the Wessex Formation. With other putative hypsilophodontids now assigned to other families, the Hypsilophodontidae currently comprises just Hypsilophodon and Vectidromeus , both from the Wessex Formation of the Isle of Wight. Hypsilophodontidae appear to be endemic to the Early Cretaceous of Europe. [ABSTRACT FROM AUTHOR]

The use of drones in the exploration and documentation of track surfaces in steep terrain, otherwise only accessible by time intensive climbing activity, is tested. Location is the Nanquan site, one of many now known footprint localities from the Lower Cretaceous Dasheng Group that has been recently exposed by local industrial excavation. It reveals an ichnofauna of sauropod, theropod, and ornithopod tracks and trackways occurring at multiple stratigraphic levels (at least 10) in a thin sequence of fine grained purple mudstones with thin sandstone units that are steeply inclined by >45°. It was therefore necessary and most efficient to map the track-bearing surfaces using drone photography. The majority of track-bearing levels reveal sauropod tracks (cf. Brontopodus , cf. Parabrontopodus ), which on some surfaces are very abundant. Large theropod tracks (cf. Grallator ) and ornithopod tracks ( Caririchnium ) also occur, but only on single horizons. The ichnofauna is evidence of repeated activity by large dinosaurs in a fluvio-lacustrine floodplain setting susceptible to periodic desiccation. The Naquan site forms part of an extensive Dasheng Group outcrop belt with multiple tracks sites, most of these containing multiple track-bearing levels. As a result of the investigation, drone techniques can be recommended as an additional tool for quick documentation, in order to get a general overview and map of the track surface. Details are relatively distinct on the achieved photographs, however, a precise study still needs direct examination and documentation by classical outline drawings or photogrammetry. [ABSTRACT FROM AUTHOR]

Zhucheng, located in eastern Shandong Province, China, is well-known for its abundant Early Cretaceous dinosaur footprints and Late Cretaceous dinosaur bone fossils. Recently, Lockley et al. (2015) presented a sketch study on the Huanglonggou tracksite in the Zhucheng area, and critically commented on our paper (H. Xu et al., 2013), which conducted a detailed and comprehensive study of the tracksite. Here, we demonstrate that some of their assumptions and comments on our work are subjective and incorrect. Tracks at the Huanglonggou tracksite, including a dominant theropod (large theropod, Grallator yangi / Paragrallator , Corpulentapus lilasia ), and subordinate sauropod, suspected ornithopod, and turtle tracks were preserved in the Yangjiazhuang Formation with estimated ages of 129 to 122 Ma, rather than in the Longwangzhuang Formation as proposed by Lockley and his associates. Contrary to Lockley et al. (2015), our mapping of the Huanglonggou tracksite exhibits the previous work by Li et al. (2011) and focuses on the 50 well-preserved trackways and their orientations. Based on the stride length to footprint size index diagram and the Grallator–Anchisauripus–Eubrontes (GAE) plexus, our statistical constraints on the three species of theropods are better than those of Lockley et al. (2015). Lockley argued that tracks at the site were preserved on at least five levels, of which the majority on level 4 were of excellent preservation. In fact, the tracks identified throughout the site have been from only one level. The false appearance of multiple levels is interpreted as the result of sedimentation at the shoreline and differential excavation of the tracksite. [ABSTRACT FROM AUTHOR]

Uppermost Cretaceous (Campanian-Maastrichtian) large ornithopod tracks are scarce in Gondwana. This record is limited to few citations in the northern Argentina, Peru and possibly Bolivia, although their ichnological affinities are still under discussion. Recently, a new vertebrate tracksite with large ornithopod tracks has been found in the Maimará locality, Jujuy province, Argentina, from the Yacoraite Formation (Maastrichtian-Danian). The best preserved track is characterized by having large and bilobed heel impression and wide and short digit impressions with blunt claw marks. This record represents the unambiguous record of large ornithopod tracks in Gondwana in the Uppermost Cretaceous, and its features allow classifying it as Hadrosauropodus . Previously, this ichnotaxon had exclusively Laurasian distribution. Therefore, this record is the first evidence of Hadrosauropodus from Gondwana expanding the geographic range of this ichnogenus. A member of Hadrosauridae is reinforced as possible trackmaker of the Hadrosauropodus tracks. Uppermost Cretaceous hadrosaurid dinosaurs are scarce in Gondwana, being the record limited to Patagonia, La Pampa province and Antarctica. Therefore, the Maimará tracks increase the knowledge of this kind of dinosaur from Gondwana. [ABSTRACT FROM AUTHOR]

The fossil record of ornithischian dinosaurs from Africa is particularly scarce and limited to a few historic localities. In this study we describe new ornithischian remains from the Albian deposits of southern Tunisia (Tataouine Governorate), represented by isolated teeth of large-bodied iguanodontians. Teeth display a wide, diamond-shaped crown with a primary ridge dividing the occlusal surface in two unequal parts and two or more secondary ridges. Hook-like denticles are present on both mesial and distal crown margins and do not display mammillae. In overall morphology, specimens are comparable to those of many Early Cretaceous basal hadrosauriforms, including isolated ornithopodan teeth from comparably-aged levels of Niger. Transversal sections of the crowns permitted identification of dental tissues, which include a thick enamel, and well developed longitudinal and transverse giant tubules. Their relative extents appear to be related to the size, thus developmental age, of the tooth. Teeth are representative of the Oum ed Diab Member, a unit characterized by coastal deposits accumulated under arid to xeric climatic conditions and dominated by fish, crocodilians, and hydraulically transported rebbachisaurid and spinosaurid remains. Sedimentological data and preservation bias strongly support selective taphonomic causes for the fossil distribution of ornithischians in southern Tunisia questioning the purported geographic and paleoecologic distribution of isolated Saharan dinosaurs. [ABSTRACT FROM AUTHOR]

Ornithopods are the least known dinosaurs within the Upper Cretaceous record of Argentina. For this reason every new record is very important to know their evolution in South America. Here, we describe a new remain of an indeterminate ornithopod recovered in the Petrobrasaurus quarry of the Puesto Hernández area, northeastern Neuquén province (Argentina), late Coniacian–early Santonian in age. MAU-Pv-PH-458 is the northernmost bone record of an ornithopod in Argentina. This is a fragmentary neural arch from the middle section of the dorsal series of similar size to Macrogryphosaurus gondwanicus . MAU-Pv-PH-458 has typical ornithopod characters such as a lateromedial narrow neural spine and transverse processes dorsoposteriorly to posteriorly oriented. It shares with Macrogryphosaurus the presence of a deep channel between the bases of the postzygapophysis, which is a continuation of the channel that separates the postzygapophyses in posterior view. MAU-Pv-PH-458 increases the ornithopod record from the Plottier Formation. [ABSTRACT FROM AUTHOR]

A new ornithopod dinosaur from the Upper Cretaceous (Maastrichtian) Snow Hill Island Formation, at James Ross Island, Antarctica is here described. This new taxon, named as Morrosaurus antarcticus gen. et sp. nov., is represented by a fragmentary right hind limb belonging to a medium-sized individual. Our phylogenetic analysis nests the new taxon in a monophyletic clade of Southern Hemisphere ornithopods that includes most Patagonian and Antarctic ornithopods. Several members of this group share a slender and bunched foot with narrow metatarsal IV, expanded chevrons, and bowed humerus without deltopectoral crest. Several features indicate that these ornithopods exhibit adaptations for a specialized cursorial mode of life. The recognition of Patagonian and Antarctic Ornithopoda belonging to a monophyletic clade reinforces palaeobiogeographical signals indicating that Patagonia, Antarctica and Australia shared a common Late Cretaceous terrestrial fauna. [ABSTRACT FROM AUTHOR]

This work provides an updated register of the main occurrences of fossilized excreta (coprolites and urolites) associated with dinosaurs found in the Brazil. The goal is to provide a relevant guide to the interpretation of the environment in the context of Gondwana. In four geographic areas, the excreta are recovered from Cretaceous sedimentary deposits in outcrops of the Bauru and São Luis basins and the Upper Jurassic aeolian deposits of the Parana Basin in the state of São Paulo. The coprolites were analyzed by X-ray diffraction and X-ray fluorescence methods. The results of these analyses reveal compositions that differ from the surrounding matrix, indicating a partial substitution of the organic material due to the feeding habits of the producers. Additionally, we describe the urolite excavations in epirelief and hyporelief, the result of gravitational flow the impact from urine jets on sand. These are associated with ornithopod and theropod dinosaur footprints preserved in the aeolian flagstones of the Botucatu Formation, Parana Basin. [ABSTRACT FROM AUTHOR]

Multiple dinosaur tracksites are known from the red beds (sandstones and siltstones) of the Hekou Group in the Lanzhou-Minhe Basin in Gansu Province, China. Among these, the most famous is the Yanguoxia No. 1 & 2 tracksite, which has an abundance of tracks from a diverse ichnofauna. Here, we describe natural casts from six new tracksites including three located near the Yanguoxia No. 1 & 2 tracksites and three from more distant tracksites (located up to 40 km from Yanguoxia). The new tracksites have all yielded isolated, large dinosaur track casts, two of which are tridactyl tracks of ornithopod and/or theropod affinity, while another eight casts are pes and manus tracks of medium-to large-sized sauropods. The predominance of sauropod track casts may reflect the fact that, by simple virtue of their large size, sauropods tracks resist weathering and are easy to find. Notably, the sauropod track casts are deep natural tracks left in soft and moist substrates with a relatively high cohesiveness. They offer a glimpse into the three-dimensional foot morphology of the sauropod trackmakers and their foot movement (locomotion), and thus are an important complement to the tracks preserved as (shallow) impressions and the trackways of the Yanguoxia No. 1 & 2 tracksite. The new tracksites suggest a lower ecological diversity than would be inferred from the Yanguoxia No. 1 & 2 tracksite. However, it is assumed that this apparent low diversity is an artifact resulting from the small sample area and the fact that all the outcrops are cross-sections where bedding planes – that could reveal small tracks and more abundant tracks and trackways – are scarce and limited to small surfaces. These new sites suggest that the distribution and frequency of dinosaur tracks within the Lanzhou-Minhe Basin is much wider than previously assumed and that many more dinosaur tracksites are likely to be discovered within the basin in the future. [ABSTRACT FROM AUTHOR]

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 1500 m² (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. [ABSTRACT FROM AUTHOR]

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 ~ 1000 m 2 , 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. [ABSTRACT FROM AUTHOR]

New fossils from the lower Barremian (Lower Cretaceous) of Spain increase the known occurrence of iguanodont dinosaurs (i.e. members of the clade Iguanodontia) in the Iberian Peninsula. A partial dentary and ischium from the fossil locality of La Cantalera 2 (Blesa Formation, municipality of Josa, Teruel province) testify to the presence of a new specimen in the early Barremian of Iberia, closely related to Delapparentia turolensis, which was previously only known in the type locality (La Maca-3, Camarillas Formation, municipality of Galve, Teruel province). These new fossils are assigned to Delapparentia turolensis (ischium) and cf. Delapparentia sp. (dentary). Moreover, the description and comparison of some of the characters of the ischium reveal that this bone is of previously unnoticed relevance for iguanodont systematics. The differences in overlapping postcranial material - observed by comparing ischial material from the provinces of Teruel and Burgos - lead us to conclude that late Hauterivian-early Barremian iguanodont diversity in Iberia consists of at least two different taxa: Delapparentia turolensis and another form closely related to Iguanodon. Additionally, dental morphotypes from La Cantalera bonebed evince the presence of at least three different iguanodonts in the lower Barremian of Iberia. [ABSTRACT FROM AUTHOR]

Abstract: The Lotus Fortress tracksite in the Qijiang National Geological Park, in Qijiang District, Chongqing Municipality consists of two distinct assemblages associated with different surfaces (Qijiang Layers 1 and 2). The lower of these two assemblages, here labeled as the “Wupus-Pteraichnus ichnoassemblage” is dominated by multiple, mainly parallel trackways of a small tridactyl and five trackways of pterosaurs (Pteraichnus). The upper surface assemblage, here labeled as the “Caririchnium ichnoassemblage”, is dominated by the tracks of ornithopods (Caririchnium lotus). Here we give a detailed description of the Pteraichnus tracks and evaluate their paleoecological significance together with other reports of pterosaur tracks from East Asia. [Copyright &y& Elsevier]

Abstract: A new ornithopod dinosaur from Antarctica, Trinisaura santamartaensis n. gen. et n. sp. is diagnosed by a unique combination of characters that includes a scapula with a spike-like acromial process with a strong and sharp lateral crest and longer than other ornithopods, a humerus with a rudimentary deltopectoral crest represented as a thickening on the anterolateral margin of the humerus, and shaft strongly bowed laterally, and an ischium gently curved along its entire length. The holotype specimen comprises vertebral and appendicular elements. The presence of axially elongate distal caudal vertebrae, pubis with long prepubic and postpubic processes, as well as a femur with a distinct anterior trochanter, pendant 4th trochanter and shallow anterior intercondylar groove constitute a combination of characters present in the Late Cretaceous Patagonian Gasparinisaura, Anabisetia and Talenkahuen. The materials were found on the surface enclosed in a hard sandstone concretion collected near the Santa Marta Cove, James Ross Island, from the lower levels of the Snow Hill Island Formation (Campanian). This is the first ornithopod taxon identified from this unit, and the second ornithischian dinosaur, after the ankylosaur Antarctopelta oliveroi. However, other ornithopod reports from nearby localities of James Ross and Vega islands in outcrops of the overlying Lopez de Bertodano Formation suggest that this clade was widely represented in the Campanian and Maastrichtian of the James Ross Basin, Antarctic continent. [Copyright &y& Elsevier]

Abstract: Fieldwork carried out during the past few years in the Algarve region (Portugal) has allowed the description of dinosaur tracks for the first time in the Mesozoic Algarve Basin. Five track levels of Early Barremian age have been described from the Santa and Salema tracksites situated near Vila do Bispo (southwest Algarve). These comprise theropod and iguanodontian footprints (Iguanodontipus isp. was identified at the Santa tracksite). A sequence of subcircular and tridactyl impressions with a characteristic morphology of ornithopod footprints with a high pace angulation value made it possible to determine how erosion changes the print morphology and to understand the sequences of subcircular impressions with a high value of pace angulation in the track record. These dinosaur footprints are preserved in marginal-marine carbonate sediments of a large inner shelf palaeoenvironment with shoals and tidal-flat areas that were periodically exposed. The warm and dry climate favoured extensive growth of algal mats and the deposition of dolomitic sediments. The discovery of these track levels has also enabled the palaeobiogeographical data available for the Early Cretaceous Iguanodontia of the Iberian Peninsula and southwestern Europe to be refined. [Copyright &y& Elsevier]

Abstract: Discrete post-embryonic teeth and bone fragments have been recovered from the matrix with the holotype skeleton (MPM‐10001) of the ornithopod dinosaur, Talenkauen santacrucensis Novas et al., 2004 (Upper Cretaceous, Argentina). The minute tooth crowns are 1mm apicobasally tall and 1.7mm mesodistally wide. The crowns are symmetrical and have a centrally located primary ridge on the lingual surface. Secondary ridges lead to five marginal denticles on both teeth. The tooth morphology is consistent with dentary teeth in euiguanodontids. There is no evidence of transport, suggesting that the material is autochthonous with respect to the adult body block of T. santacrucensis (MPM‐10001). Steeply inclined wear facets on the lingual surface and associated microstriae support the conclusion that the minute teeth were from a post-embryonic euiguanodontid dinosaur rather than early stage replacement teeth. The morphology, size, and wear of the teeth and small bone fragments found in the body block of MPM‐10001 suggest that this material belongs to a neonatal T. santacrucensis. This is the first record of neonatal ornithopod remains from Gondwana. [Copyright &y& Elsevier]

Abstract: A new ornithischian dinosaur, Yueosaurus tiantaiensis gen. et sp. nov., is erected based on a partial postcranial skeleton from the Liangtoutang Formation (Aptian–Cenomanian) of Zhejiang Province, China. It differs from other ornithischians in possessing the following unique combination of characters: prominent and slightly ventrally directed cervical parapophyses; anteroposteriorly narrow neural spines on caudal vertebrae; scapula with a ventroscapular groove, supraglenoidal buttress, supraglenoid fossa, and a strong anteroventral expansion of the scapular blade. Yueosaurus represents the first basal ornithopod taxon from southeastern China. It expands our understanding of the Cretaceous dinosaurian fauna of Zhejiang Province. [Copyright &y& Elsevier]

Abstract: We report the first sauropod remains recorded in the Guichón Formation, western Uruguay. The materials belong to a middle-sized sauropod represented by more than one individual, and among other remains include more than fifty caudal centra. Close to the bones, several eggshell fragments resembling Sphaerovum erbeni were found. We discuss the biostratigraphic implications of these findings, which for the first time allow us to confidently refer the Guichón Formation to the Late Cretaceous. The combination of several synapomorphies such as a biconvex first caudal centrum, strongly procoelous middle and distal caudal centra, and a pyramidal astragalus suggests that the sauropod remains belong to a derived lithostrotian, probably related to Pellegrinisaurus powelli, Baurutitan britoi and Alamosaurus sanjuanensis. A few isolated teeth (now lost) referred by Frederich von Huene in 1934 to ornithomimid theropods and ornithischians are herein reinterpreted as belonging to indeterminate theropods and basal iguanodontians. [Copyright &y& Elsevier]

Abstract: An isolated tooth from the late Maastrichtian strata of the Scollard Formation of Alberta, Canada, has been identified as the only record of a non-hadrosaurid hadrosauriform from the Maastrichtian of North America. Here, we demonstrate that this identification is in error and that the tooth pertains to an indeterminate ceratopsid. In addition, we provide full documentation of the published collection of Scollard Formation fossils from which the tooth was originally derived. [Copyright &y& Elsevier]

Abstract: More than 125 footprints of theropods from the Cretaceous Longwangzhuang Formation have been mapped in a preliminary study at a site in the Zhucheng region of China. The tracks represent at least three morphotypes. The largest morphotype is a large theropod (footprint length ∼30cm) represented by a single trackway and an isolated natural cast. At least 10 trackways assigned to the new ichnospecies Corpulentapus lilasia represent a medium-sized biped (footprint length ∼13cm) with very short, wide, robust, ‘tulip-shaped’ tracks and long steps (∼5×footprint length), and a short central digit (III) indicating weak mesaxony. Corpulentapus trackways are narrow and theropod-like even though track morphology is convergent with the footprints of some ornithopods. The third morphotype, made by a medium-sized grallatorid track maker (ichnogenus Paragrallator), is about the same size (∼13cm) as the robust morphotype, but far more elongate and gracile, with an elongate central digit (III) indicating strong mesaxony. This ichnotaxon requires detailed comparison with Grallator sensu stricto. The contrast in morphology between the two common morphotypes is striking and demonstrates that two distinct medium-sized taxa of presumed theropod affinity frequented the same habitat in significant numbers. [Copyright &y& Elsevier]

Abstract: A screenwashed microvertebrate site, the Mile 175 locality, in the Morrison Formation of Wyoming has yielded more than 3000 elements of actinopterygian fish and indicates that fish were not as rare in some parts of the formation as previously supposed. Actinopterygians are represented by diverse teeth and tooth-bearing bone fragments, fin elements, and thousands of scales and scale fragments that can be divided into three distinct morphotypes. Lungfish are rare, represented by nine toothplates and toothplate fragments that are provisionally assigned to Potamoceratodus. Tetrapods recovered from the Mile 175 locality include indeterminate salamanders, turtles, choristoderes, a squamate, goniopholid crocodyliforms, theropod and ornithopod dinosaurs, and several mammals, including Docodon and indeterminate multituberculates. Salamanders are represented by just a few indeterminate vertebrae. The turtle fauna includes numerous small shell fragments and limb elements. The authors assign a tooth-bearing jaw fragment and several vertebrae to the choristodere Cteniogenys, whereas a sole vertebra is the only squamate fossil recovered. Theropod dinosaurs are well represented by several teeth, as is the ornithopod dinosaur Othnielosaurus. Similarly, several mammalian tooth and jaw fragments can be referred to either Docodon or Multituberculata indet. Dominance of the sample by aquatic and semi-aquatic taxa suggests the paleodepositional environment was a permanent water source. Many of the specimens appear to represent small and presumably ontogenetically young individuals of larger, known taxa in the Morrison Formation, and the site includes the northernmost occurrences of several taxa in the formation. Screenwashing efforts at several other previously quarried large-vertebrate sites in the Morrison Formation have shown promising results for recovering previously unidentified taxa. [Copyright &y& Elsevier]

Abstract: A new taxon of ornithopod dinosaur is described as Siamodon nimngami nov. gen, nov. sep., on the basis of a well-preserved maxilla from the Khok Kruat Formation (Aptian) of northeastern Thailand. An isolated tooth and a braincase are referred to this taxon, and the status of other ornithopod specimens from Thailand and Laos is discussed. S. nimngami nov. gen, nov. sep. is considered as an advanced iguanodontian, apparently close to Probactrosaurus, from which it differs by various characters of the maxilla. Siamodon is an addition to the already long list of advanced iguanodontian taxa from the late Early Cretaceous of Asia. The diversity and abundance of these forms may suggest that advanced iguanodontians first appeared in Asia, before spreading to other parts of the world. [Copyright &y& Elsevier]

Abstract: Twelve trackways of ornithopods from Lower Cretaceous lacustrine margin deposits of the Jindong Formation represent new dinosaur trackways described from Korea. The site, discovered during highway construction, was rescued by removing the most important trackways to the Korean Natural Heritage Center in Daejeon, where they are on permanent display. The new ichnotaxon Ornithopodichnus masanensis ichnogen. et ichnosp. nov. is recognized as a distinctive robust tridactyl track, slightly wider than long (l/w ratio=0.91), with positive (inward) rotation. The toe prints are very thick, broad and U-shaped, resulting in a trefoil outline with a smoothly rounded hind margin. Digit III is short and projects anteriorly much less than digit II and IV (= weak mesaxony). Divarication of digits II-IV is about 70° with interdigital angle II-III larger than III-IV. Trackway width is narrow and the stride length/track length ratio is about 4.2–4.6. The Ornithopodichnus trackways evidently represent gregarious blunt-toed Iguanodon-like bipedal ornithopods, although poorly preserved manus traces are discerned in a few trackways. Ornithopodichnus is distinct from other well known iguanodontid tracks that display much stronger mesaxony and indicates a polarity in ornithopod foot morphology that can be verified by reference to known foot skeletons. [Copyright &y& Elsevier]

Abstract: The remains of an ornithopod dinosaur from the Upper Barremian (Lower Cretaceous) of Auxerre (Burgundy, France) are described. They consist of several vertebrae and a fragmentary scapula. Despite obvious morphological and dimensional affinities with the species Iguanodon bernissartensis, the state of the specimen does not allow any identification more precise than Iguanodontia indet. Reappraisal of the French Upper Barremian record of medium and large-sized ornithopods reveals that no specimen can be definitely determined to the specific level. [Copyright &y& Elsevier]

Abstract: The small ornithopod dinosaur Hypsilophodon foxii, from the Early Cretaceous (Barremian) of the Isle of Wight, England, is one of the best known of all dinosaurs; however, the reported presence of dermal armour in this taxon is poorly understood. We reassess the evidence for dermal armour: in all specimens in which they can be identified the plate-like structures formerly identified as armour are associated with the lateral surfaces of the distal sections of the anterior dorsal ribs. Comparison with the ornithopods Talenkauen and Thescelosaurus suggests that these structures do not represent armour, but are instead mineralised cartilaginous intercostal plates. Such plates were probably widespread in basal ornithopods, but have not been recognised to date due to incomplete preservation or variation in the timing and degree of mineralisation. [Copyright &y& Elsevier]

Abstract: Criteria for designating dinosaur genera are inconsistent; some very similar species are highly split at the generic level, other anatomically disparate species are united at the same rank. Since the mid-1800s the classic genus Iguanodon has become a taxonomic grab-bag containing species spanning most of the Early Cretaceous of the northern hemisphere. Recently the genus was radically redesignated when the type was shifted from nondiagnostic English Valanginian teeth to a complete skull and skeleton of the heavily built, semi-quadrupedal I. bernissartensis from much younger Belgian sediments, even though the latter is very different in form from the gracile skeletal remains described by Mantell. Currently, iguanodont remains from Europe are usually assigned to either robust I. bernissartensis or gracile I. atherfieldensis, regardless of location or stage. A stratigraphic analysis is combined with a character census that shows the European iguanodonts are markedly more morphologically divergent than other dinosaur genera, and some appear phylogenetically more derived than others. Two new genera and a new species have been or are named for the gracile iguanodonts of the Wealden Supergroup; strongly bipedal Mantellisaurus atherfieldensis Paul (2006. Turning the old into the new: a separate genus for the gracile iguanodont from the Wealden of England. In: Carpenter, K. (Ed.), Horns and Beaks: Ceratopsian and Ornithopod Dinosaurs. Indiana University Press, Bloomington, pp. 69–77) (holotype BMNH R5764) which possesses a camptosaur-like ilial shape, and the long snouted, long bodied, small hipped, semi-bipedal Dollodon bampingi gen. nov. sp. nov. (holotype IRSNB 1551) which has a shallow ilium. Insufficiently diagnostic I. hoggii is removed from the earlier Camptosaurus. Poorly described I. dawsoni, I. fittoni and I. hollingtoniensis are removed from the much later and more derived Iguanodon and considered Ornithopoda incertae sedis pending redescription. The synonymy of I. fittoni and I. hollingtoniensis has not been confirmed. A set of remains of similar age to I. fittoni and I. hollingtoniensis appear to combine a specialized, elongate dentary with massive arms: it either belongs to one of the contemporary taxa, or is a new, unnamed taxon. There has recently been a tendency to consider iguanodonts spatially remote from I. bernissartensis to be members of or very similar to the type species, but reanalysis finds that I. orientalis is not a junior synonym of I. bernissartensis and is a nomen dubium, and that basal I. lakotaensis is not a member of Iguanodon and accordingly is assigned the new genus Dakotadon gen. nov. (holotype SDSM 8656). Dakotadon is probably basal to Iguanodon and not an iguanodontoid. The higher taxonomy of iguanodontoids is confused due to phylogenetic problems, and inconsistent definitions of the Iguanodontidae (which as currently defined appears to be limited to Iguanodon) and Hadrosauroidea. Mantellisaurus and especially Dollodon, for instance, are probably more derived than Iguanodon: they may be hadrosauroids depending on which phylogenetic definition of the term is preferred. [Copyright &y& Elsevier]

Abstract: The fragmentary remains of a juvenile rhabdodontid ornithopod from the Coal-bearing Complex of the Gosau Group (Lower Campanian, Grünbach syncline) at Muthmannsdorf near Wiener Neustadt, Lower Austria are revised. The material, probably belonging to a single individual, includes a right dentary (lectotype of Iguanodon suessi Bunzel, 1871, designated herein), teeth, a fragmentary parietal, fragments of scapula, ?radius, femur, tibia, two vertebrae (lost) and a manual ungual. The lectotype dentary does not provide clear autapomorphies or sufficient diagnostic features to determine its position within the Rhabdodontidae at generic level. By this “Iguanodon suessi” Bunzel, 1871 and the genus “Mochlodon” Seeley, 1881, to which it was latter referred as type species, cannot be characterized sufficiently by differential diagnosis and these are best considered nomina dubia. Based upon combined character comparisons (mainly postcranial features) the Muthmannsdorf ornithopod is referred herein to Zalmoxes Weishampel, Jianu, Csiki and Norman, 2003, a genus so far known from the late Maastrichtian of Romania. It probably but not evidently represents a yet unnamed species, most closely related to Zalmoxes shqiperorum Weishampel, Jianu, Csiki and Norman, 2003. At the present state of knowledge the Austrian material is not further diagnostic at the species level and kept in open nomenclature as Zalmoxes sp. [Copyright &y& Elsevier]

Abstract: The first dinosaur remains are described from the Upper Cretaceous (Santonian) Csehbánya Formation, Iharkút, Bakony Mts, Hungary. Eight teeth of herbivorous dinosaurs (Rhabdodontidae indet. Nodosauridae indet.) and four teeth belonging to Theropoda indet. are presented. There are also hundreds of fish, frog, turtle and crocodile bones and teeth embedded in fluvial sand of an alluvial plain. Palaeobiogeographic connections towards Provence, the eastern Alps, and southern Carpathians indicate that the Adriatic microplate bearing the fossiliferous succession was an island temporarily connected to the European continent during Late Cretaceous time. [Copyright &y& Elsevier]

The Cambridge Greensand Member (lower Cenomanian: Upper Cretaceous) has yielded a diverse fauna of terrestrial and marine tetrapods, whose remains are largely reworked from the underlying Gault Formation (upper Albian: Lower Cretaceous). Here, we re-describe two of the non-avian dinosaur taxa named from this unit, ' Eucercosaurus tanyspondylus ' Seeley, 1879 and ' Syngonosaurus macrocercus ' Seeley, 1879, both of which have been referred to as either ankylosaurs or ornithopods but whose validity has not been rigorously assessed for over a century. Both taxa are interpreted as the remains of iguanodontian dinosaurs but possess no clear diagnostic features. Nevertheless, although ' Eucercosaurus ' and ' Syngonosaurus ' are nomina dubia they do indicate that iguanodontians were common components of the Cambridge Greensand tetrapod fauna and, alongside ' Trachodon cantabrigiensis ' Lydekker, 1888, represent an important datum for understanding iguanodontian distributions during the mid-Cretaceous. • ' Eucercosaurus tanyspondylus ' and ' Syngonosaurus macrocercus ' are re-described. • They are both shown to be indeterminate iguanodontian dinosaurs, not ankylosaurs. • These taxa show that ornithopods were common in the Cambridge Greensand fauna. • The Cambridge Greensand provides key distribution data for mid-Cretaceous dinosaurs. [ABSTRACT FROM AUTHOR]

The bone histology of the Antarctic ornithopods Trinisaura santamartaensis and Morrosaurus antarcticus from the Upper Cretaceous (Campanian-Maastrichtian) is here studied. With the purpose to obtain information regarding their growth pattern, we analyse the bone histology of appendicular elements from the holotype specimens of both species. The cortical bone of the studied elements is constituted by fibro-lamellar tissue, with vascular canals mostly showing in a longitudinal and reticular arrangement, suggesting an accelerated growth. The cortical bone tissue is interrupted by lines of arrested growth (LAGs) and annuli. The study reveals that both the holotypes of Trinisaura and Morrosaurus were sexually mature subadults at the time of death (i.e. they died before reach somatic maturity). The growth pattern of these Antarctic ornithopods is similar to that reported for the related taxon Gasparinisaura , which lived in lower latitudes, as well as for the Australian ornithopods, taxa that inhabited polar latitudes during the Early Cretaceous. This contrasts with the pattern reported for more derived ornithopods (i.e. hadrosaurids) and ceratopsians from the Northern Hemisphere, whose growth dynamics vary in different latitudes. In this regard, Gondwanan ornithopods would present a preadaptation for endure in environments with great temperature changes along the year. [ABSTRACT FROM AUTHOR]

Macrogryphosaurus gondwanicus is the largest Elasmaria (Dinosauria, Ornithischia) known up to the date, from the Upper Cretaceous of Patagonia. The present contribution provides a detailed description of Macrogryphosaurus anatomy based on the holotype and only known specimen. This dinosaur presents several unique features along its vertebral column that distinguishes it from other ornithopods: the neck is notably elongated by the acquisition of an additional cervical vertebra, having 10 cervical plus 14 dorsal vertebrae, being the number of dorsals minor than in other taxa, which usually have 16. This implies that Macrogryphosaurus represents a new ornithopod morphotype, with long neck and short thorax. Moreover, three autapomorphies are here added to the original diagnosis of Macrogryphosaurus : presence of poorly developed diapophyses in the cervical vertebrae, anterior and posterior processes on the boat-shaped haemal arches, and a pubic foot in the postpubic process. The dorsoventral length of haemal arches indicate the ventral limit of the M. caudofemoralis longus and their posterior tapering so as the dorsal limit of the M. ilio-ischiocaudalis and its posterior ascension and dominance in the posterior-most portion of tail, resembling to the tail of some coelurosaur dinosaurs. [ABSTRACT FROM AUTHOR]