Spinosaurids are among the most distinctive and yet poorly-known of large-bodied theropod dinosaurs, a situation exacerbated by their mostly fragmentary fossil record and competing views regarding their palaeobiology. Here, we report two new Early Cretaceous spinosaurid specimens from the Wessex Formation (Barremian) of the Isle of Wight. Large-scale phylogenetic analyses using parsimony and Bayesian techniques recover the pair in a new clade within Baryonychinae that also includes the hypodigm of the African spinosaurid Suchomimus. Both specimens represent distinct and novel taxa, herein named Ceratosuchops inferodios gen. et sp. nov. and Riparovenator milnerae gen. et sp. nov. A palaeogeographic reconstruction suggests a European origin for Spinosauridae, with at least two dispersal events into Africa. These new finds provide welcome information on poorly sampled areas of spinosaurid anatomy, suggest that sympatry was present and potentially common in baryonychines and spinosaurids as a whole, and contribute to updated palaeobiogeographic reconstructions for the clade.

Trackways of ornithopods are well-known from the Lower Cretaceous of Europe, North America, and East Asia. For historical reasons, most large ornithopod footprints are associated with the genus Iguanodon or, more generally, with the family Iguanodontidae. Moreover, this general category of footprints is considered to be sufficiently dominant at this time as to characterize a global Early Cretaceous biochron. However, six valid ornithopod ichnogenera have been named from the Cretaceous, including several that are represented by multiple ichnospecies: these are Amblydactylus (two ichnospecies); Caririchnium (four ichnospecies); Iguanodontipus, Ornithopodichnus originally named from Lower Cretaceous deposits and Hadrosauropodus (two ichnospecies); and Jiayinosauropus based on Upper Cretaceous tracks. It has recently been suggested that ornithopod ichnotaxonomy is oversplit and that Caririchnium is a senior subjective synonym of Hadrosauropodus and Amblydactylus is a senior subjective synonym of Iguanodontipus. Although it is agreed that many ornithopod tracks are difficult to differentiate, this proposed synonymy is questionable because it was not based on a detailed study of the holotypes, and did not consider all valid ornithopod ichnotaxa or the variation reported within the six named ichnogenera and 11 named ichnospecies reviewed here. We therefore emphasize the need to base comparisons between ichnotaxa on type material, and not on selected referred material. It is concluded that there is considerable variation in the morphology of the holotypes, as well as variation in size and quality of the samples and the mode of preservation. Conversely, there is considerable overlap in morphology among other tracks that have been informally attributed to these ichnotaxa. These factors make it difficult to synonymize any of the existing ichnotaxa without detailed revision of the samples from which the type material originates. Nevertheless, a review of the type material of all ichnotaxa is presented as a basis for further discussion and, as a first step, the ichnofamily Iguanodontipodidae is proposed to accommodate Amblydactylus, Caririchnium and Iguanodontipus,

Hanover Point on the Isle of Wight, England, is a Lower Cretaceous (Barremian) site yielding a large number of dinosaur footprints from the Wessex Formation. These footprints, hitherto often referred to as 'Iguanodon' tracks, have generated interest and speculation since the beginning of the Victorian era. Today, Hanover Point largely yields sandstone casts (convex hyporeliefs) of footprints but also includes some impressions (concave epireliefs), a few of which form short trackways. The majority belongs to large ornithopods, many with foot lengths in excess of 50 cm. Theropods and the occasional thyreophoran track are also represented. The site represents the Wessex Formation within the Wealden Group and can be described ichnologically as a category 3a deposit. Most of the large ornithopod footprints have a distinctive quadripartite morphology and are best assigned to the ichnogenus Caririchnium or in some cases Amblydactylus. Few are morphologically compatible with Iguanodontipus which was described from pre-Wealden deposits and appears to be little represented in the Wealden ichnofaunas.

The Wealden exposures on the Isle of Wight have long been noted for their dinosaur footprints and trackways and represent a unique ichnological resource. However, with a few notable exceptions, these ichnites remain largely unstudied and documentation has been sporadic and often concentrated on a few particular sites. Thus, their context within the Lower Cretaceous is poorly understood. The vertebrate ichnological record of the Wessex Sub-basin is currently being re-assessed. We review the main sites containing dinosaur footprints on the Isle of Wight. We also look at previously-known sites, and present new research using techniques such as photogrammetry to accurately record, preserve, and distribute ichnological data, especially data recorded in the dynamic foreshore and cliff environments, where many trace fossils are frequently lost as a result of human activity, weathering, erosion, and changing marine dynamics. Although the ichnoassemblages of the island's Wealden facies are dominated by ornithopod tracks including Caririchnium and Amblydactylus, we also report the first occurrence of the ankylosaurian track Tetrapodosaurus in both the Wessex and Vectis Formations, alongside the previously reported stegosaurian Deltapodus, as well as the occurrence of tracks left by saurichian tracemakers.

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Postcranial elements (cervical, sacral and caudal vertebrae, as well as ilium, rib and limb bone fragments) belonging to a gigantic tetanuran theropod were recovered from the basal unit (the White Rock Sandstone equivalent) of the Vectis Formation near Compton Chine, on the southwest coast of the Isle of Wight. These remains appear to pertain to the same individual, with enormous dimensions similar to those of the Spinosaurus holotype and exceeding those of the largest European theropods previously reported. A combination of features—including the presence of spinodiapophyseal webbing on an anterior caudal vertebra—suggest that this is a member of Spinosauridae, though a lack of convincing autapomorphies precludes the identification of a new taxon. Phylogenetic analysis supports spinosaurid affinities but we were unable to determine a more precise position within the clade weak support for a position within Spinosaurinae or an early-diverging position within Spinosauridae were found in some data runs. Bioerosion in the form of curved tubes is evident on several pieces, potentially related to harvesting behaviour by coleopteran bioeroders. This is the first spinosaurid reported from the Vectis Formation and the youngest British material referred to the clade. This Vectis Formation spinosaurid is unusual in that the majority of dinosaurs from the Lower Cretaceous units of the Wealden Supergroup are from the fluviolacustrine deposits of the underlying Barremian Wessex Formation. In contrast, the lagoonal facies of the upper Barremian–lower Aptian Vectis Formation only rarely yield dinosaur material. Our conclusions are in keeping with previous studies that emphasise western Europe as a pivotal region within spinosaurid origination and diversification.