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This year marks the one hundred sixty-fourth anniversary of Richard Owen’s (1841) description of the first sauropod—Cetiosaurus, the “whale lizard”—on the basis of vertebrae and limb elements from localities across England. Although these remains “had been examined by Cuvier and pronounced to be cetaceous” (Buckland 1841:96), Owen (1841:458–459) demonstrated the saurian affinities of Cetiosaurus on the basis of several features, including the absence of epiphyses (growth plates) on caudal vertebrae (fig. 1.1). He differentiated Cetiosaurus from other extinct saurians on the basis of its large size and characteristics of its vertebrae (see Upchurch and Martin 2003:215). Owen (1841:462) concluded his initial description with this assessment: “The vertebrae, as well as the bones of the extremities, prove its marine habits . . . the surpassing bulk and strength of the Cetiosaurus were probably assigned to it with carnivorous habits, that it might keep in check the Crocodilians and Plesiosauri.” He regarded Cetiosaurus as a crocodilian by the “form of the long bones” and “the toes being terminated by strong claws” (Owen 1842:102), but this assessment was based on limited anatomical evidence (Owen 1875:27). Key data emerged with the discovery of abundant Cetiosaurus bones in Oxfordshire by John Phillips. Thomas Huxley examined this “splendid series of remains” before the publication of Phillips’ (1871) monograph and was the first to place Cetiosaurus within Dinosauria (Iguanodontidae [Huxley, 1869:35]). Phillips (1871) interpreted Cetiosaurus as a planteating dinosaur and hypothesized that its limb bones were “suited for walking.” He could not rule out the possibility that it was amphibious, however, concluding that it was a “marsh-loving or riverside animal.” Owen (1875:27) later acquiesced, referring Cetiosaurus to the Dinosauria because of its four sacral vertebrae. He admitted that it may have had some terrestrial capabilities but concluded that Cetiosaurus was an estuarine or marine animal based on its “organ of swimming,” the tail (Owen 1875:41). These early interpretations, based on somewhat limited samples, were followed by the discovery of abundant sauropod skeletons in western North America and eastern Africa during

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, © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113, 721–736.

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.

PROBACTROSAURUS GOBIENSIS ROZHDESTVENSKY, 1952 (NORMAN, 2002) Remains of this taxon indicate the presence of a medium-sized iguanodontian (attaining ∼ 6 m in length) collected from the Ulansuhai Formation (Turonian), Maortu, China (Kobayashi & Lu, 2003). Teeth and jaws The dentary crowns of this taxon (Norman, 2002: figs 14–16) are narrower and less ornate than those described in Hy. fittoni (Fig. 37). The marginal denticles support mammillations, but these are less numerous than in the case of Hy. fittoni and the denticles do not form a curved shelf as they do in Hy. fittoni. The roots of the teeth are also fluted for the compaction of adjacent functional and replacement crowns that form the dental magazine. There are at least two replacement crowns in each alveolus in the deeper portions of the dentary and the occlusal surface is broad because it comprises at least two dentary crowns, unlike Hy. fittoni. The dentary of Prob. gobiensis is comparatively shorter and deeper than that of Hy. fittoni with a larger and deeper area devoted to the dental magazine as well as a tall, perpendicular coronoid process (Norman, 2002: fig. 12). Axial skeleton What is known of the dorsal vertebral series (Norman, 2002: fig. 17) shows neither the thickening of the articular margins of the centra, nor any clear indication of the narrow and very tall neural spines that are displayed in Hy. fittoni (this is confirmed by reference to the shape of the anterior caudals – Norman, 2002: fig. 18). Appendicular skeleton Most of the postcranial anatomy of Prob. gobiensis (Norman, 2002: figs 20–33) appears to be gracile and generally comparable to that seen in M. atherfieldensis (Norman, 1986) rather than Hy. fittoni. The forearm and manus are notably slender and lightly built in Prob. gobiensis, and the pollex ungual is small, narrow, and conical (Norman, 2002: figs 22–26), in marked contrast to these structures in Hy. fittoni. The ischial shaft is heavy, robust, and J-shaped (Norman, 2002: fig. 29) and resembles that seen in Hy. fittoni., Published as part of Norman, David B., 2015, On the history, osteology, and systematic position of the Wealden (Hastings group) dinosaur Hypselospinus fittoni (Iguanodontia: Styracosterna), pp. 92-189 in Zoological Journal of the Linnean Society 173 (1) on page 158, DOI: 10.1111/zoj.12193, http://zenodo.org/record/5330460, {"references":["Rozhdestvensky AK. 1952. Otkritiye iguanodonta v Mongolii. [Discovery of iguanodonts in Mongolia]. Doklady Akademiya Nauk CCCP LXXXIV: 1243 - 1246.","Kobayashi Y, Lu J-C. 2003. A new ornithomimid dinosaurian with gregarious habits from the Late Cretaceous of China. Acta Palaeontologica Polonica 48: 235 - 259.","Norman DB. 1986. On the anatomy of Iguanodon atherfieldensis (Ornithischia: Ornithopoda). Bulletin de l'Institut Royal des Sciences Naturelles de Belgique 56: 281 - 372."]}

PROBACTROSAURUS GOBIENSIS ROZHDESTVENSKY, 1952 (NORMAN, 2002) Remains of this taxon indicate the presence of a medium-sized iguanodontian (attaining ∼ 6 m in length) collected from the Ulansuhai Formation (Turonian), Maortu, China (Kobayashi & Lu, 2003). Teeth and jaws The dentary crowns of this taxon (Norman, 2002: figs 14–16) are narrower and less ornate than those described in Hy. fittoni (Fig. 37). The marginal denticles support mammillations, but these are less numerous than in the case of Hy. fittoni and the denticles do not form a curved shelf as they do in Hy. fittoni. The roots of the teeth are also fluted for the compaction of adjacent functional and replacement crowns that form the dental magazine. There are at least two replacement crowns in each alveolus in the deeper portions of the dentary and the occlusal surface is broad because it comprises at least two dentary crowns, unlike Hy. fittoni. The dentary of Prob. gobiensis is comparatively shorter and deeper than that of Hy. fittoni with a larger and deeper area devoted to the dental magazine as well as a tall, perpendicular coronoid process (Norman, 2002: fig. 12). Axial skeleton What is known of the dorsal vertebral series (Norman, 2002: fig. 17) shows neither the thickening of the articular margins of the centra, nor any clear indication of the narrow and very tall neural spines that are displayed in Hy. fittoni (this is confirmed by reference to the shape of the anterior caudals – Norman, 2002: fig. 18). Appendicular skeleton Most of the postcranial anatomy of Prob. gobiensis (Norman, 2002: figs 20–33) appears to be gracile and generally comparable to that seen in M. atherfieldensis (Norman, 1986) rather than Hy. fittoni. The forearm and manus are notably slender and lightly built in Prob. gobiensis, and the pollex ungual is small, narrow, and conical (Norman, 2002: figs 22–26), in marked contrast to these structures in Hy. fittoni. The ischial shaft is heavy, robust, and J-shaped (Norman, 2002: fig. 29) and resembles that seen in Hy. fittoni.

The history of discovery and interpretation of several dinosaurs collected from quarries near the town of Hastings during the latter half of the 19th century is more complicated than it should be. Samuel Husbands Beckles and Charles Dawson collected several large ornithopod skeletons from this area, but just a few bones from these skeletons were subsequently described and interpreted (principally) by Richard Owen and Richard Lydekker. All these specimens merited recognition because they had the potential to contribute to an on-going debate about the anatomical structure and relationships of the iconic Wealden dinosaur Iguanodon. Unfortunately, no detailed description of these important skeletons was published in later years. Furthermore, previously known associations of bones and even provenance information, linked to the specimens that were gradually acquired by the Natural History Museum, are unclear. Confusion may have arisen because Richard Lydekker used the private collector Charles Dawson as a voluntary curatorial assistant. This account documents the past work on the osteology of material that can be attributed to Hypselospinus fittoni. Nearly all such material is described here for the first time, and every effort has been made to re-establish associations between bones as well as provenance information. A skeletal reconstruction of Hypselospinus is attempted on the basis of the hypodigm. Most of the on-going confusion concerning the affinity of this material with either Hy. fittoni or its sympatric contemporary Barilium dawsoni has been resolved. Hypselospinus fittoni (Lydekker, 1889) is rediagnosed on the basis of this new and relatively comprehensive anatomical description, and this animal is compared with known contemporary and closely related taxa. Some recently published accounts claiming to be revisions of the taxonomy of Wealden ‘iguanodonts’, including material belonging to the hypodigm of Hy. fittoni, have failed to adhere to basic taxonomic principles and have caused more confusion than was strictly necessary. The systematic position of Hypselospinus is reassessed cladistically. The cladistic analysis forms the basis for a revised hierarchical classification of derived ornithopods. The consensus topology generated by the systematic analysis has been used to explore the phylogenetic history of these dinosaurs and create an internally consistent classificatory hierarchy (phylogenetic definitions and Linnaean diagnoses are given for critical positions in the topology). This analysis suggests that there is a fundamental split amongst the more derived (clypeodontan) ornithopod ornithischians into the clades Hypsilophodontia and Iguanodontia. There is evidence for anatomical parallelism and convergence (homoplasy) particularly between large-bodied representatives of both clades. Hypselospinus is one of the earliest known styracosternan iguanodontians and displays anatomical characteristics that presage the evolution of the extraordinarily abundant and diverse hadrosaurs of the latest Cretaceous (Campanian−Maastrichtian). These observations cast fresh light on the phylogeny, classification, diversity, and biology of derived ornithopods. There is little doubt that Hy. fittoni could have been understood far better more than a century ago. That this statement is undoubtedly true is reflected in the century of doubt and confusion that has surrounded this taxon and its original incarnation as Iguanodon fittoni.

Resume Le para-taxon biorecord Superret- croton , defini par Hughes et al. en 1979 dans le sous-bassin du Wessex (Angleterre), est pour la premiere fois mis en evidence dans les facies wealdiens du « cran aux Iguanodons » de Bernissart (formation des Argiles de Sainte-Barbe, bassin de Mons, Belgique). Ce morphotype temoigne de la presence d’angiospermes. Il est equivalent au taxon morphographique Stellatopollis hughesii Penny, 1986. En utilisant son extension verticale definie dans les coupes de reference bien datees des sous-bassins du Weald et du Wessex (Angleterre), un âge compris entre le Barremien moyen et l’Aptien basal est attribue sediments a facies wealdien situes a 322 m de profondeur dans le « cran aux Iguanodons ». Cette datation confirme, d’une part, l’âge Barremien hypothetique, anterieurement avance sur la base de l’evolution morphologique des Iguanodontidae. Elle precise, d’autre part, l’âge du debut de la subsidence dans le bassin de Mons, contemporain d’une baisse du niveau eustatique de deuxieme ordre et probablement associe a la dissolution d’anhydrites profondes. Pour citer cet article : J. Yans et al., C. R. Palevol 4 (2005) .

A new dinosaur of Early Cretaceous age was recently discovered in the Gobi Desert of northwest China. It is more closely related to Late Cretaceous hadrosaurids than to Early Cretaceous iguanodontids. It occupies the most basal position in the phylogeny of all duck-billed dinosaurs, or the Hadrosauroidea. This early hadrosauroid sheds new light on the origin of the herbivorous feeding specializations of the Late Cretaceous duck-billed dinosaurs, and corroborates the view that the Iguanodontidae and the Hadrosauroidea are monophyletic clades, with the former characterized by an enlarged maxilla as the main mechanism for mastication, and the latter diagnosed by a smaller yet more mobile maxilla with an elaborate dental battery, separated by a diastema from the enlarged premaxilla. Our study also suggests that the Hadrosauroidea had most likely originated in Asia in the Early Cretaceous before this clade diversified and spread to other Laurasian continents during the Late Cretaceous. (C) 2003 Elsevier Ltd. All rights reserved.

The skull material of a new iguanodontian dinosaur, Fukuisaurus tetoriensis gen. et sp. nov., discovered from the fluvial deposits of the Lower Cretaceous Kitadani Formation, Tetori Group, Fukui Prefecture, Japan, is described here. Some features of Fukuisaurus show affinities with Iguanodon, Ouranosaurus, and Altirhinus, referred to as Iguanodontidae by some. A phylogenetic analysis using mainly cranial characters shows that Fukuisaurus is a definitive derived non-hadrosaurid iguanodontian and implies that Fukuisaurus is more derived than the clade of Iguanodon + Ouranosaurus and more basal to the clade of Altirhinus, Probactrosaurus, Eolambia, Protohadros, Bactrosaurus, Telmatosaurus, and hadrosaurids. It also supports that Iguanodontidae is paraphyletic by the exclusion of Altirhinus as suggested previously. The presence of Fukuisaurus indicates a wider geographical distribution of the group in eastern Asia. The occurrences of derived non-hadrosaurid iguanodontians from the Kitadani Formation ...

Resume Un gisement paralique inedit, d’âge Cenomanien inferieur, avec du bois fossile, de l’ambre insectifere et des restes de vertebres, a ete decouvert sur l’estran de la presqu’ile de Fouras (Charente-Maritime, France), a la suite d’une tempete qui a temporairement ote du littoral les nappages de cordons sableux et de vasieres. L’assemblage de bois fossiles contient trois taxons de coniferes ( Agathoxylon , Podocarpoxylon , Brachyoxylon ) et un Ginkgoxylon . Les insectes de l’ambre correspondent a des Dipteres, des Hymenopteres et des Homopteres. Les restes de vertebres sont principalement representes par des carapaces de tortues terrestres (Solemydidae), des vertebres de serpents ( Simoliophis ) et des ossements de dinosaures, appartenant probablement au genre Iguanodon . Pour citer cet article : D. Neraudeau et al., C. R. Palevol 2 (2003).

The Upper Cretaceous (Maastrichtian) outcrop of EIs Nerets (Tremp, Lleida) has yielded sorne sauropod bones: a fragment of centrum from a dorsal vertebra, an incomplete humerus, femur and tibia. This material is identified as Titanosauridae indet. based on the following synapomorphies: acuminate pleurocoelous posterior outline, cancellous osseus tissue, humeral prominent posterior supracondylar ridges, prominent fourth trochanter. Additional material from EIs Nerets includes three caudal centra identified as Iguanodontidae indet. The site of Sant Roma d' Abella, Upper Cretaceous (Maastrichtian) in age, is located at Della (Lleida). Fourteen caudal centra coming from this locality have been identified as Hadrosauridae indet., based on a single postulated synapomorphy, the hexagonal outline of the centra. El yacimiento del Cretácico superior (Maastrichtiense) de EIs Nerets (Tremp, Lleida) ha proporcionado diversos huesos de saurópodo: un fragmento de centro de vértebra dorsal, un húmero incompleto, fémur y tibia. Este material es identificado como Titanosauridae indet. en base a las siguientes sinapomorfías: contorno posterior pleurocélico acuminado, tejido óseo cancelar, crestas supracondilares prominentes en el húmero, cuarto trocánter desarrollado. Material adicional procedente de EIs Nerets incluye tres centros caudales identificados como Iguanodontidae indet. El yacimiento de Sant Roma d'AbelIa, situado en la cuenca de Delia (Lleida), ha proporcionado catorce centros caudales identificados como Hadrosauridae indet. mediante una única sinapomorfía postulada, el contorno hexagonal de los centros.

The Upper Cretaceous (Maastrichtian) outcrop of EIs Nerets (Tremp, Lleida) has yielded sorne sauropod bones: a fragment of centrum from a dorsal vertebra, an incomplete humerus, femur and tibia. This material is identified as Titanosauridae indet. based on the following synapomorphies: acuminate pleurocoelous posterior outline, cancellous osseus tissue, humeral prominent posterior supracondylar ridges, prominent fourth trochanter. Additional material from EIs Nerets includes three caudal centra identified as Iguanodontidae indet. The site of Sant Roma d' Abella, Upper Cretaceous (Maastrichtian) in age, is located at Della (Lleida). Fourteen caudal centra coming from this locality have been identified as Hadrosauridae indet., based on a single postulated synapomorphy, the hexagonal outline of the centra.El yacimiento del Cretácico superior (Maastrichtiense) de EIs Nerets (Tremp, Lleida) ha proporcionado diversos huesos de saurópodo: un fragmento de centro de vértebra dorsal, un húmero incompleto, fémur y tibia. Este material es identificado como Titanosauridae indet. en base a las siguientes sinapomorfías: contorno posterior pleurocélico acuminado, tejido óseo cancelar, crestas supracondilares prominentes en el húmero, cuarto trocánter desarrollado. Material adicional procedente de EIs Nerets incluye tres centros caudales identificados como Iguanodontidae indet. El yacimiento de Sant Roma d'AbelIa, situado en la cuenca de Delia (Lleida), ha proporcionado catorce centros caudales identificados como Hadrosauridae indet. mediante una única sinapomorfía postulada, el contorno hexagonal de los centros.

Note on Iguanodon Taxonomy The taxonomy of Iguanodon has been problematic ever since Mantell (1825) erected the genus without a type species. Holl (1829) provided the species name I. anglicum (emended to anglicus: Norman 1986) shortly thereafter based upon the teeth described by Mantell, including the lectotype NHMUK R 2392 (Norman 1986). However, these teeth possess no features that would definitively demarcate them from the teeth of other, better known iguanodontian species (Norman 1986; Charig & Chapman 1998). Thus, I. anglicus was declared a nomen dubium and I. bernissartensis, by virtue of its complete lectotype skeleton from Belgium, was made the type species of Iguanodon (Charig & Chapman 1998). Furthermore, some species and specimens formerly regarded as pertaining to Iguanodon have been recently removed (Norman & Barrett 2002; Paul 2007, 2008; Galton 2009; Norman 2010); the name Mantellisaurus Paul, 2007 is used herein for “ I.” atherfieldensis, Owenodon Galton, 2009 for “ I.” hoggii, and Barilium Norman, 2010 and Hypselospinus Norman, 2010 respectively for “ I.” dawsoni and “ I.” fittoni. Norman (2010) discussed NHMUK 28660 and illustrated it in medial view (Norman 2010: fig. 10 C), suggesting that it might be referable to Barilium, which occurs in the middle Valanginian Wadhurst Clay Formation with Hypselospinus. However, there are several reasons for not referring NHMUK 28660 to either of the Wadhurst Clay taxa. The unit in which NHMUK 28660 was found, the Grinstead Clay Member of the Tunbridge Wells Sand Formation, is stratigraphically above and slightly younger than the Wadhurst Clay Formation (Allen & Wimbledon 1991; Radley 2004; Rawson 2006). More importantly, NHMUK 28660 differs from the two basal iguanodont dentaries from the Wadhurst Clay: NHMUK R 1834 and NHMUK R 1831. NHMUK R 1834 is a partial associated skeleton that includes a partial left dentary, numerous vertebral centra, a fragmented right scapula, a well preserved right ilium, and several pedal elements; the specimen is herein considered referable to Barilium due to the similar morphologies (e.g., smoothly convex dorsal margin) shared by its ilium and NHMUK R 802, the holotype ilium of Barilium (contra Norman 2010, who referred NHMUK R 1834 to Hypselospinus). The ventrally inflected rostral ramus of the dentary of NHMUK R 1834 differs from the straight rostral ramus of NHMUK 28660 (Figs 1 A, 2 A), suggesting that they do not represent the same taxon. Dentaries of basal iguanodonts known from multiple specimens from the same locality and horizon (e.g., Camptosaurus dispar [USNM 4281, 5818, 5961; YPM 1886, 1888] from Quarry 13 in the Morrison Formation, Iguanodon bernissartensis [IRSNB 1536, 1561, 1639] from Bernissart, and Eolambia caroljonesa [CEUM 34357, 34447, 35482, 35714, 52139, 52995] from Eolambia # 2 Quarry in the Mussentuchit Member, Cedar Mountain Formation) indicate that there is no intraspecific variation in the morphology of the rostral ramus, i.e. straight versus ventrally inflected, and that this character is probably taxonomically informative. NHMUK R 1831, a right dentary, is part of an associated skeleton with elements catalogued under numbers NHMUK R 1832 – 33 and NHMUK R 1835 – 36. The taxonomic identification of this skeleton is undecided, with Paul (2008) regarding it as a potential new taxon and Norman (2010) referring it to Hypselospinus; however, the specimen includes only a shard of an ilium and a very poorly preserved femur, and thus possesses no overlapping features that would support referral to Hypselospinus (based on the holotype NHMUK R 1635 and referred material comprising the holotype of the subjective junior synonym “ Iguanodon hollingtoniensis ”; Norman 2010). NHMUK R 1831 is similar to NHMUK 28660 in its straight rostral ramus (Fig. 1 B), but differs in having a longer diastema (though not as long as suggested by Paul 2008; ATM pers. obs.; Norman 2010) and teeth with more prominent accessory ridges arising from the marginal denticles directly mesial to the primary ridge. The coronoid process of NHMUK R 1831 is broken both at its base and apex, thus rendering its inclination and expansion, or lack thereof, difficult to evaluate. Given that there are two named taxa (Barilium and Hypselospinus) and two different dentary morphologies (NHMUK R 1834, referred herein to Barilium, and NHMUK R 1831) from the Wadhurst Clay, it would be convenient to refer NHMUK R 1831 and associated postcranial specimens to Hypselospinus; however, this is not supportable in the absence of shared morphologies and overlapping material. This situation is akin to that of the derived titanosaurs Nemegtosaurus (known from a skull) and Opisthocoelicaudia (known from a partial postcranium) from the Nemegt Formation of Mongolia (Wilson 2005), i.e. the possibilities that the specimens represent the same taxon and that they represent different diagnostic taxa must be considered equally likely given the known material. Both NHMUK R 1834 and NHMUK R 1831 lack the autapomorphic row of foramina observed in NHMUK 28660 (see below). These differences indicate that NHMUK 28660 should not be referred to the same taxon as either of the Wadhurst Clay dentaries. Because the distinctive dentary NHMUK 28660 was found in the same unit (Grinstead Clay Member of the Tunbridge Wells Sand Formation) and vicinity as the non-diagnostic teeth of Iguanodon anglicus, it would be tempting to refer NHMUK 28660 to I. anglicus and thus render that taxon diagnostic. However, there are two reasons for not doing so. Firstly, the isolated dentary teeth of I. anglicus do not share any synapomorphies with the in situ tooth of NHMUK 28660 to the exclusion of other iguanodontian specimens, such as NHMUK R 1831, Owenodon hoggii (NHMUK R 2998), Iguanodon bernissartensis (MIWG 1997.55), and Mantellisaurus atherfieldensis (NHMUK R 5764). Secondly, although NHMUK 28660 and the teeth of I. anglicus both came from quarries near Cuckfield, it is evident that more than one lithostratigraphic horizon was exposed in those quarries (Gallois & Worssam 1993). Among the numerous isolated and disarticulated iguanodontian bones found near Cuckfield, some are embedded in a tan, well sorted, fine-grained sandstone matrix, whilst others are in dark brown, poorly sorted, coarser sandstone. The disarticulated nature of the bones and presence of more than one bone-bearing layer make it impossible to refer disparate elements to the same taxon with any certainty. Considering these factors, it is best to continue to regard “ Iguanodon anglicus ” as a nomen dubium and to create the novel genus and species Kukufeldia tilgatensis for NHMUK 28660. Institutional abbreviations AMNH American Museum of Natural History, New York, NY, USA ANSP Academy of Natural Sciences, Philadelphia, PA, USA CEUM College of Eastern Utah Prehistoric Museum, Price, UT, USA CM Carnegie Museum of Natural History, Pittsburgh, PA, USA DMNH Denver Museum of Nature and Science, Denver, CO, USA HERM Hull and East Riding Museum, Hull, UK IRSNB Institut royal des Sciences naturelles de Belgique, Brussels, Belgium IVPP Institute of Vertebrate Paleontology and Paleoanthropology, Beijing, China MIWG Museum of Isle of Wight Geology (Dinosaur Isle Museum), Sandown, UK MNHN Muséum national d’Histoire naturelle, Paris, France MSM Mesa Southwest Museum (now Arizona Museum of Natural History), Mesa, AZ, USA NHMUK Natural History Museum (formerly BMNH, British Museum of Natural History), London, UK OXFUM Oxford University Museum of Natural History, Oxford, UK PIN Palaeontological Institute, Moscow, Russia QM Queensland Museum, South Brisbane, Australia SDSM South Dakota School of Mines and Technology, Rapid City, SD, USA SMU Southern Methodist University Shuler Museum of Paleontology, Dallas, TX, USA UMNH Utah Museum of Natural History, Salt Lake City, UT, USA USNM National Museum of Natural History, Washington, DC, USA YPM Yale University Peabody Museum of Natural History, New Haven, CT, USA

A nearly complete right dentary originally noted by Mantell in 1848 is redescribed. The specimen, NHMUK 28660, was discovered in a quarry near Cuckfield, West Sussex, from the same formation as the original teeth of Iguanodon anglicus. Fresh examination reveals that NHMUK 28660 exhibits a single autapomorphy (a row of foramina extending from the ventral surface of the symphysis onto the lateral surface of the dentary) and a unique combination of characters that distinguish it from all other iguanodontian dentaries. In light of this and because I. anglicus is regarded as a nomen dubium to which additional material cannot be unambiguously referred, NHMUK 28660 is made the holotype of the new genus and species Kukufeldia tilgatensis.

Note on Iguanodon Taxonomy The taxonomy of Iguanodon has been problematic ever since Mantell (1825) erected the genus without a type species. Holl (1829) provided the species name I. anglicum (emended to anglicus: Norman 1986) shortly thereafter based upon the teeth described by Mantell, including the lectotype NHMUK R 2392 (Norman 1986). However, these teeth possess no features that would definitively demarcate them from the teeth of other, better known iguanodontian species (Norman 1986; Charig & Chapman 1998). Thus, I. anglicus was declared a nomen dubium and I. bernissartensis, by virtue of its complete lectotype skeleton from Belgium, was made the type species of Iguanodon (Charig & Chapman 1998). Furthermore, some species and specimens formerly regarded as pertaining to Iguanodon have been recently removed (Norman & Barrett 2002; Paul 2007, 2008; Galton 2009; Norman 2010); the name Mantellisaurus Paul, 2007 is used herein for ��� I.��� atherfieldensis, Owenodon Galton, 2009 for ��� I.��� hoggii, and Barilium Norman, 2010 and Hypselospinus Norman, 2010 respectively for ��� I.��� dawsoni and ��� I.��� fittoni. Norman (2010) discussed NHMUK 28660 and illustrated it in medial view (Norman 2010: fig. 10 C), suggesting that it might be referable to Barilium, which occurs in the middle Valanginian Wadhurst Clay Formation with Hypselospinus. However, there are several reasons for not referring NHMUK 28660 to either of the Wadhurst Clay taxa. The unit in which NHMUK 28660 was found, the Grinstead Clay Member of the Tunbridge Wells Sand Formation, is stratigraphically above and slightly younger than the Wadhurst Clay Formation (Allen & Wimbledon 1991; Radley 2004; Rawson 2006). More importantly, NHMUK 28660 differs from the two basal iguanodont dentaries from the Wadhurst Clay: NHMUK R 1834 and NHMUK R 1831. NHMUK R 1834 is a partial associated skeleton that includes a partial left dentary, numerous vertebral centra, a fragmented right scapula, a well preserved right ilium, and several pedal elements; the specimen is herein considered referable to Barilium due to the similar morphologies (e.g., smoothly convex dorsal margin) shared by its ilium and NHMUK R 802, the holotype ilium of Barilium (contra Norman 2010, who referred NHMUK R 1834 to Hypselospinus). The ventrally inflected rostral ramus of the dentary of NHMUK R 1834 differs from the straight rostral ramus of NHMUK 28660 (Figs 1 A, 2 A), suggesting that they do not represent the same taxon. Dentaries of basal iguanodonts known from multiple specimens from the same locality and horizon (e.g., Camptosaurus dispar [USNM 4281, 5818, 5961; YPM 1886, 1888] from Quarry 13 in the Morrison Formation, Iguanodon bernissartensis [IRSNB 1536, 1561, 1639] from Bernissart, and Eolambia caroljonesa [CEUM 34357, 34447, 35482, 35714, 52139, 52995] from Eolambia # 2 Quarry in the Mussentuchit Member, Cedar Mountain Formation) indicate that there is no intraspecific variation in the morphology of the rostral ramus, i.e. straight versus ventrally inflected, and that this character is probably taxonomically informative. NHMUK R 1831, a right dentary, is part of an associated skeleton with elements catalogued under numbers NHMUK R 1832 ��� 33 and NHMUK R 1835 ��� 36. The taxonomic identification of this skeleton is undecided, with Paul (2008) regarding it as a potential new taxon and Norman (2010) referring it to Hypselospinus; however, the specimen includes only a shard of an ilium and a very poorly preserved femur, and thus possesses no overlapping features that would support referral to Hypselospinus (based on the holotype NHMUK R 1635 and referred material comprising the holotype of the subjective junior synonym ��� Iguanodon hollingtoniensis ���; Norman 2010). NHMUK R 1831 is similar to NHMUK 28660 in its straight rostral ramus (Fig. 1 B), but differs in having a longer diastema (though not as long as suggested by Paul 2008; ATM pers. obs.; Norman 2010) and teeth with more prominent accessory ridges arising from the marginal denticles directly mesial to the primary ridge. The coronoid process of NHMUK R 1831 is broken both at its base and apex, thus rendering its inclination and expansion, or lack thereof, difficult to evaluate. Given that there are two named taxa (Barilium and Hypselospinus) and two different dentary morphologies (NHMUK R 1834, referred herein to Barilium, and NHMUK R 1831) from the Wadhurst Clay, it would be convenient to refer NHMUK R 1831 and associated postcranial specimens to Hypselospinus; however, this is not supportable in the absence of shared morphologies and overlapping material. This situation is akin to that of the derived titanosaurs Nemegtosaurus (known from a skull) and Opisthocoelicaudia (known from a partial postcranium) from the Nemegt Formation of Mongolia (Wilson 2005), i.e. the possibilities that the specimens represent the same taxon and that they represent different diagnostic taxa must be considered equally likely given the known material. Both NHMUK R 1834 and NHMUK R 1831 lack the autapomorphic row of foramina observed in NHMUK 28660 (see below). These differences indicate that NHMUK 28660 should not be referred to the same taxon as either of the Wadhurst Clay dentaries. Because the distinctive dentary NHMUK 28660 was found in the same unit (Grinstead Clay Member of the Tunbridge Wells Sand Formation) and vicinity as the non-diagnostic teeth of Iguanodon anglicus, it would be tempting to refer NHMUK 28660 to I. anglicus and thus render that taxon diagnostic. However, there are two reasons for not doing so. Firstly, the isolated dentary teeth of I. anglicus do not share any synapomorphies with the in situ tooth of NHMUK 28660 to the exclusion of other iguanodontian specimens, such as NHMUK R 1831, Owenodon hoggii (NHMUK R 2998), Iguanodon bernissartensis (MIWG 1997.55), and Mantellisaurus atherfieldensis (NHMUK R 5764). Secondly, although NHMUK 28660 and the teeth of I. anglicus both came from quarries near Cuckfield, it is evident that more than one lithostratigraphic horizon was exposed in those quarries (Gallois & Worssam 1993). Among the numerous isolated and disarticulated iguanodontian bones found near Cuckfield, some are embedded in a tan, well sorted, fine-grained sandstone matrix, whilst others are in dark brown, poorly sorted, coarser sandstone. The disarticulated nature of the bones and presence of more than one bone-bearing layer make it impossible to refer disparate elements to the same taxon with any certainty. Considering these factors, it is best to continue to regard ��� Iguanodon anglicus ��� as a nomen dubium and to create the novel genus and species Kukufeldia tilgatensis for NHMUK 28660. Institutional abbreviations AMNH American Museum of Natural History, New York, NY, USA ANSP Academy of Natural Sciences, Philadelphia, PA, USA CEUM College of Eastern Utah Prehistoric Museum, Price, UT, USA CM Carnegie Museum of Natural History, Pittsburgh, PA, USA DMNH Denver Museum of Nature and Science, Denver, CO, USA HERM Hull and East Riding Museum, Hull, UK IRSNB Institut royal des Sciences naturelles de Belgique, Brussels, Belgium IVPP Institute of Vertebrate Paleontology and Paleoanthropology, Beijing, China MIWG Museum of Isle of Wight Geology (Dinosaur Isle Museum), Sandown, UK MNHN Mus��um national d���Histoire naturelle, Paris, France MSM Mesa Southwest Museum (now Arizona Museum of Natural History), Mesa, AZ, USA NHMUK Natural History Museum (formerly BMNH, British Museum of Natural History), London, UK OXFUM Oxford University Museum of Natural History, Oxford, UK PIN Palaeontological Institute, Moscow, Russia QM Queensland Museum, South Brisbane, Australia SDSM South Dakota School of Mines and Technology, Rapid City, SD, USA SMU Southern Methodist University Shuler Museum of Paleontology, Dallas, TX, USA UMNH Utah Museum of Natural History, Salt Lake City, UT, USA USNM National Museum of Natural History, Washington, DC, USA YPM Yale University Peabody Museum of Natural History, New Haven, CT, USA, Published as part of Mcdonald, Andrew T., Barrett, Paul M. & Chapman, Sandra D., 2010, A new basal iguanodont (Dinosauria: Ornithischia) from the Wealden (Lower Cretaceous) of England, pp. 1-43 in Zootaxa 2569 on pages 2-4, DOI: 10.5281/zenodo.197354, {"references":["Mantell, G. (1825) Notice on the Iguanodon, a newly discovered fossil reptile, from the sandstone of Tilgate Forest, in Sussex. Philosophical Transactions of the Royal Society of London, 115, 179 - 186.","Holl, F. (1829) Handbuch der Petrefactenkunde, Part I. Quedlingberg, Leipzig, 232 pp.","Norman, D. B. (1986) On the anatomy of Iguanodon atherfieldensis (Ornithischia: Ornithopoda). Bulletin de l'Institut Royal des Sciences Naturelles de Belgique, 56, 281 - 372.","Charig, A. J. & Chapman, S. D. (1998) Iguanodon Mantell, 1825 (Reptilia, Ornithischia): proposed designation of Iguanodon bernissartensis Boulenger in Beneden, 1881 as the type species, and proposed designation of a lectotype. Bulletin of Zoological Nomenclature, 55, 99 - 104.","Norman, D. B. & Barrett, P. M. (2002) Ornithischian dinosaurs from the Lower Cretaceous (Berriasian) of England. Special Papers in Palaeontology, 68, 161 - 189.","Paul, G. S. (2007) 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.","Paul, G. S. (2008) A revised taxonomy of the iguanodont dinosaur genera and species. Cretaceous Research, 29, 192 - 216.","Galton, P. M. (2009) Notes on Neocomian (Lower Cretaceous) ornithopod dinosaurs from England - Hypsilophodon, Valdosaurus, \" Camptosaurus \", \" Iguanodon \" - and referred specimens from Romania and elsewhere. Revue de Paleobiologie, Geneve, 28, 211 - 273.","Norman, D. B. (2010) A taxonomy of iguanodontians (Dinosauria: Ornithopoda) from the lower Wealden Group (Cretaceous: Valanginian) of southern England. Zootaxa, 2489, 47 - 66.","Allen, P. & Wimbledon, W. A. (1991) Correlation of NW European Purbeck - Wealden","Radley, J. (2004) Demystifying the Wealden of the Weald (Lower Cretaceous, south-east England). Open University Geological Society Journal, 25, 6 - 16.","Rawson, P. F. (2006) Cretaceous: sea levels peak as the North Atlantic opens. In: Brenchley, P. J. & Rawson, P. F. (Eds.), The Geology of England and Wales, 2 nd Edition. The Geological Society of London, Bath, pp. 365 - 394.","Wilson, J. A. (2005) Redescription of the Mongolian sauropod Nemegtosaurus mongoliensis Nowinski (Dinosauria: Saurischia) and comments on Late Cretaceous sauropod diversity. Journal of Systematic Palaeontology, 3, 283 - 318.","Gallois, R. W. & Worssam, B. C. (Eds) (1993) Geology of the country around Horsham: Memoir for 1: 50,000 geological sheet 302 (England and Wales). Her Majesty's Stationary Office, London, 130 pp."]}

Se describen restos óseos de Iguanodontidae, posiblemente Iguanodon atherfieldensis Hooley, 1925, procedentes de niveles marinos del Hauteriviense inferior de Mirambel (Provincia de Teruel, NE de España). La fauna asociada sugiere un ambiente muy próximo a la línea costera. La cronostratigrafía de estas capas es inferior a las capas rojas de Morella de las que, geográficamente, están muy próximas.

Crocodylians possess the same thoracic epaxial muscles as most other saurians, but M. transversospinalis is modified by overlying osteoderms. Compared with crocodylians, the thoracic epaxial muscles of birds are reduced in size, disrupted by the synsacrum, and often modified by intratendinous ossification and the notarium. A phylogenetic perspective is used to determine muscle homologies in living archosaurs (birds and crocodylians), evaluate how the apparent disparity evolved, and reconstruct the thoracic epaxial muscles in ornithopod dinosaurs. The avian modifications of the epaxial musculoskeletal system appear to have coevolved with the synsacrum and notarium. The lattice of ossified tendons in iguanodontoidean dinosaurs (Hadrosauridae and Iguanodontidae) is homologized to M. transversospinalis in crocodylians and M. longus colli dorsalis, pars thoracica in birds. Birds have an arrangement of tendons within M. longus colli dorsalis, pars thoracica identical to that observed in the epaxial ossified tendons of iguanodontoid dinosaurs. Moreover, many birds (such as grebes and turkeys) ossify these tendons, resulting in a two- or three-layered lattice of ossified tendons, a morphology also seen in iguanodontoid dinosaurs. Although the structure of M. transversospinalis appears indistinguishable between birds and iguanodontoid dinosaurs, intratendinous ossification within this epaxial muscle evolved convergently. Anat Rec Part A, 288A:782–793, 2006. © 2006 Wiley-Liss, Inc.

Norman, David B. (2002): On Asian ornithopods (Dinosauria: Ornithischia). 4. Probactrosaurus Rozhdestvensky, 1966. Zoological Journal of the Linnean Society 136 (1): 113-144, DOI: 10.1046/j.1096-3642.2002.00027.x, URL: https://academic.oup.com/zoolinnean/article-lookup/doi/10.1046/j.1096-3642.2002.00027.x

PROBACTROSAURUS ALASHANICUS PIN 2232/40-3 ��� caudal vertebra; 40-5, 40-6 metatarsal block II, III (left) PIN 2232/41-1 ��� dentary; 41-2 ��� scapula; 41-3 ��� scapula; 41-4 ��� humerus (incomplete ��� l) PIN 2232/42-1 ��� dentary (r)., Published as part of Norman, David B., 2002, On Asian ornithopods (Dinosauria: Ornithischia). 4. Probactrosaurus Rozhdestvensky, 1966, pp. 113-144 in Zoological Journal of the Linnean Society 136 (1) on page 116, DOI: 10.1046/j.1096-3642.2002.00027.x, http://zenodo.org/record/5436207

Up to the moment, two species of Iguanodon had been cited in the Lower Cretaceous of Spain: I. cf. atherfieldensis and I. bernissartensis. In general, the size has been the diagnostic character to separate I. atherfieldensis from I. bernissartensis, and many of the spanish Iguanodon remains would be regarded as Iguanodontidae indet or Iguanodon sp. A third species (1. cf. fittoni) is situated in the Jurassic-Cretaceous transition

Up to the moment, two species of Iguanodon had been cited in the Lower Cretaceous of Spain: I. cf. atherfieldensis and I. bernissartensis. In general, the size has been the diagnostic character to separate I. atherfieldensis from I. bernissartensis, and many of the spanish Iguanodon remains would be regarded as Iguanodontidae indet or Iguanodon sp. A third species (1. cf. fittoni) is situated in the Jurassic-Cretaceous transition

The Upper Cretaceous (Maastrichtian) outcrop of EIs Nerets (Tremp, Lleida) has yielded sorne sauropod bones: a fragment of centrum from a dorsal vertebra, an incomplete humerus, femur and tibia. This material is identified as Titanosauridae indet. based on the following synapomorphies: acuminate pleurocoelous posterior outline, cancellous osseus tissue, humeral prominent posterior supracondylar ridges, prominent fourth trochanter. Additional material from EIs Nerets includes three caudal centra identified as Iguanodontidae indet. The site of Sant Roma d' Abella, Upper Cretaceous (Maastrichtian) in age, is located at Della (Lleida). Fourteen caudal centra coming from this locality have been identified as Hadrosauridae indet., based on a single postulated synapomorphy, the hexagonal outline of the centra.

The new outerop of Santa Bárbara (Galve, Province of Teruel, Spain, here provisionally considered as Barremian-Aptian in age) has yielded sorne autopodial pieces especially of the hind limbo There are a tibial distal portion, tarsus, metatarsal fragmenta and several phalanges of the three digits, especially of digit IV. Within the family Iguanodontidae, two groups of genera can be recognized, One of them, more progressive, has the tendency towards the disappearance of the first digit and the shortening of the acropodial elements. The material from Santa Bárbara c1early belongs to the last group, and its morphology indicates the genus Iguonodon, Based on morfological criteria it is not possible, up to now, to separate I. bernissartensis from I. mantelli, it can be done only based on size criteria. So, the greatest part of the material of Santa Bárbara is identified as l. cf. mantelli, though this outcrop has yielded two phalanges of the size of I. bernissartensis too.El nuevo yacimiento de Santa Bárbara (Galve, Teruel, considerado provisionalmente como Barremiense-Aptiense) ha proporcionado una serie de elementos apendiculares, especialmente del autópodo posterior. En este material se incluye una porción distal de tibia, tarso, fragmentos metatarsales y diversas falanges, especialmente del cuarto dígito. Parece poder distinguirse, dentro de la familia Iguanodontidae, dos grupos de géneros. Uno de ellos, más progresivo, tiende a la desaparición del dedo uno y al acortamiento de los elementos acropodiales . El material de Santa Bárbara se incluye claramente en este grupo. Su morfología indica Su pertenencia al género Iguanodon. Al nivel actual de información, no parece posible distinguir los autópodos posteriores de I. mantelli e I. bernissartesis en base a criterios morfológicos, sino tan sólo a tamaño. Desde este punto de vista, la mayoría del material de Santa Bárbara se identifica como I. cf. mantelli, aunque el yacimiento ha proporcionado igualmente dos falanges de la talla de I.bernissartesis.

An ensemble of 10 footprints forming a trackway, lower Cretaceous (possibly Valanginian) in age, have been found in Cornago (La Rioja, Spain). The imprints are tridactylous, belonging to a ornithopod dinosaur of graviportal and mesaxonic type. If one considers the family Iguanodontidae as a "evolutive grade" the trackmaker can probably be included within this taxon. Two methodological proposals (Alexander, 1976 & Demathieu, 1984) have been considered to estimate the speed of the trackmaker. Both methods have yielded similar values of speed (5.39 and 4.67 Km/h, respectively). In order to minimize the error introduced in the Alexander's method, it is proposed to carry out a statistical analysis (within the taxon in which the trackmaker is included) for the estimate of the length ratio mean between the autopodial imprint and the Iimb. The speed values are coincident with the inferred speed values proposed for larger ornithopods.Han sido halladas un conjunto de 10 icnitas formando una traza en niveles del Cretácico inferior (posiblemente Valanginiense) de la región de Cornago (La Rioja). Las huellas son tridáctilas, pertenecientes a un dinosaurio ornitópodo de tipo graviportal y mesaxónico. Considerando la familia Iguanodontidae como un "grado evolutivo" el responsable de la traza puede ser probablemente incluido en dicho taxón familiar. Se ha calculado la velocidad del autor de la pista en base a dos propuestas metodológicas: Alexander (1976) y Demathieu (1984). Ambos métodos proporcionan valores semejantes de la velocidad (5.39 y 4.67 Km/h., respectivamente). Para tratar de minimizar los errores introducidos en el procedimiento elaborado por el primer autor se propone la realización de un análisis estadístico (dentro del taxón al que se asigne al autor de la traza) que estime la relación media entre la longitud de la huella autopodial y la de la extremidad. Los valores obtenidos para la velocidad de desplazamiento coinciden con las propuestas de estimación de velocidad en ornitópodos de gran talla.

The study of a great part of the material found during the excavation work carried out by a team of the «Institut de Paleontologia de Sabadell» and other paleontologists of the universities of Madrid and Bellaterra, in the basin of Tremp (Maastrichtiense) in 1984 and 1985 has made possible the recognition of: 1.o A large sized Crocodilian, attributable to an adult animal of the Alligatoridae family, comparable to Crocodilus affluvelensis . 2.° Dinosaur remains atributed to three difIerent families: Atlantosauridae (represented by a large sized Sauropod, probably Hypselosaurus ); Iguanodontidae (afI. Rhabdodon , medium sized Omithopod); and Hadrosauridae ( Ortbomerus , small sized). 3.° Dinosaur's footprints, not very well preserved, medium and large sized, attributable to biped Omithopod. The fauna remains were always found unconnected, scattered all over large areas and with no signs of depredation. The sort of materials found reveal a certain transport which caused a selective action over the remains. Later, the efIects of the orogenic processes suffered by this area in the Tertiary period would combine with this transport.