THE SAUROPOD DINOSAUR TURIASAURUS RIODEVENSIS IN THE LATE JURASSIC OF PORTUGAL MATEUS, Octávio, New University of Lisbon (CICEGe-FCT) & Museum of Lourinhã, Lisboa, Portugal A partial sauropod was found in 1996 in Vale Pombas, north of Lourinhã, Central West of Portugal, in the Lourinhã Formation, top of Amoreira Porto Novo member dated as c. 150 M.a. (Early Tithonian, Late Jurassic) and is currently housed at Museum of Lourinhã, in Portugal. The specimen (ML368) comprises a complete tooth with root, anterior chevron and almost complete right forelimb including partial scapula, complete coracoid, humerus, ulna, radius, metacarpals I, III and V, phalanx, and ungual phalanx I. It can be ascribed to Turiasaurus riodevensis, which was previously described from the Villar del Arzobispo Formation at Riodeva (Teruel, Spain). Characters shared with T. riodevensis holotype include: curvature and asymmetry of tooth crown, expansion of crown, outline of humerus, medial deflection of the proximal end of humerus, shape and prominence of deltopectoral crest, vertical ridge in the distal half of the ulna (considered as diagnostic of Turiasauria), configuration of metacarpals, and bone proportions. It differs from T. riodevensis holotype by the smaller size and the more rectangular ungual phalanx in lateral view. The sediments from which the Riodeva specimen was recovered were previsouly thought to be Tithonian to Berriasian in age. The presence of this species in Portugal, in beds confidently dated as Early Tithonian, may allow a more precise date for the Riodeva type locality of early Tithonian in age. The humerus of the Portuguese T. riodevensis is 152 cm long. Although shorter than the Spanish specimen (790 mm), it represents a large individual. All adult sauropods recovered in Portugal thus far are very large individuals: Dinheirosaurus (estimated body length is 20- 25 m), Lusotitan (humerus length estimated to be 205 cm), Lourinhasaurus (femur length: 174 cm), and Turiasaurus here reported. The lack of of small or medium adult body-size sauropods in the Late Jurassic of Portugal, suggests browsing niches thought to be occupied by smaller forms, could be have been available for other dinosaurs, like the long necked stegosaur Miragaia longicollum.

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Abstract: The paleontological collections of the Museum of Lourinhã, in Portugal, has a rich paleontological collection, particularly of Late Jurassic dinosaurs of the Lourinhã Formation (Kimmeridgian-Tithonian). Most salient highlights comprehend the following dinosaur holotype specimens: stegosaur Miragaia longicollum, theropod Lourinhanosaurus antunesi, sauropod Dinheirosaurus lourinhanensis, ornithopod Draconyx loureiroi, theropod Allosaurus europaeus, and, a mammal, Kuehneodon hahni. Other dinosaur specimens are referred including the nest and eggs and embryos of Lourinhanosaurus. Portugal is very productive in Late Jurassic vertebrates, being the seventh country bearing more dinosaur taxa.

The richness of Late Jurassic vertebrates in Portugal is known since the 19th century by Paul Choffat, Henri Sauvage and other. The Kimmeridgian Guimarota fauna assemblage is the best known, followed by the fauna of Lourinhã formation. Here is presented an attempt to provide a checklist of the reptiles and amphibians of the Late Jurassic. Amphibia: Lissamphibia (Celtedens, cf. Marmorerpeton, Discoglossidae indet.). Chelonia: Eucryptodira (Pleurosternidae indet., Platychelyidae indet., Plesiochelys cf. etalloni, Plesiochelys choffati, Anosteirinae indet.). Squamata: Scincomorpha (Becklesius hoffstetteri; Paramacellodus sp., Saurillodon proraformis, S. henkeli, S. cf. obtusus). Squamata: Anguimorpha (Dorsetisaurus pollicidens, Parviraptor estesi). Crown Lepidosauromorpha (Marmoretta sp.). Choristodera: Cteniogenidae (Ctenogenys reedi). Sauropterygia: Plesiosauria: Cryptoclidoidea: Cryptoclididae indet. Crocodylomorpha (Lisboasaurus estesi, L. mitrocostatus). Crocodyliformes: Neosuchia (Machimosaurus hugii, Goniopholis cf. simus, Goniopholis baryglyphaeus, cf. Bernissartia, Atoposauridae, Theriosuchus guimarotae, cf. Alligatorium, Metriorhynchus sp.). Pterosauria (Rhamphorhynchus sp., Pterodactylus sp.). Dinosauria: Theropoda (Ceratosaurus sp. , Torvosaurus sp., Lourinhanosaurus antunesi, Allosaurus europaeus, Cf. Compsognathus sp., cf. Richardoestesia sp., Dromaeosaurinae indeter., Velociraptorinae indeter., cf. Archaeopteryx sp., aff. Paronychodon). Dinosauria: Sauropoda: Eusauropoda (Dinheirosaurus lourinhanensis, Lourinhasaurus alenquerensis, Lusotitan atalaiensis, Apatosaurus sp.). Dinosauria: Ornithischia: Thyreophora (Dacentrurus armatus, Stegosaurus sp., Dracopelta zbyszewskii). Dinosauria: Ornithischia: Ornithopoda (Phyllodon henkeli, Dryosaurus sp., Hypsilophodon sp., Alocodon kuehnei, Trimucrodon cuneatus, Draconyx loureiroi).

Book of abstracts of the 5th Symposium on Mesozoic and Decapod Crustaceans

Although nonavian theropod have received considerable interest in the last years, their ontogeny still remains poorly understood, especially the ontogenetical changes affecting their skull (Rauhutand Fechner, 2005). The quadrate, for instance, is preserved in several embryos and juvenile specimens belonging to many clades of theropods such as the Tyrannosauridae (Carr, 1999), Compsognathidae (Dal Sasso and Maganuco, 2011), Therizinosauroidea (Kúndrat et al., 2007), Oviraptoridae (Norell et al., 1994; Norell et al., 2001; Weishampel et al., 2008) and Troodontidae (Varrichio et al., 2002) but very little is usually said about the anatomy of this bone and no one has ever investigated ontogenetical variation in the nonavian theropod quadrate. The discovery of two quadrates belonging to embryos of the sinraptorid Lourinhanosaurus antunesi from Portugal and five isolated quadrates pertaining to juvenile, subadult and adult specimens of Spinosauridae from Morocco fills this gap and allows some ontogenetic information to be drawn for this bone in these two specific clades of Theropoda.

A newly discovered dinosaur track-assemblage from the Upper Jurassic Lourinha˜ Formation (Lusitanian Basin, central-west Portugal), comprises medium- to large-sized sauropod tracks with well-preserved impressions of soft tissue anatomy, stegosaur tracks and tracks from medium- to large-sized theropods. The 400-m-thick Lourinha˜ Formation consists of mostly aluvial sediments, deposited during the early rifting of the Atlantic Ocean in the Kimmeridgian and Tithonian. The stratigraphic succession shows several shifts between flood-plain mud and fluvial sands that favour preservation and fossilization of tracks. The studied track-assemblage is found preserved as natural casts on the underside of a thin bivalve-rich carbonate bed near the Tithonian–Kimmeridgian boundary. The diversity of the tracks from the new track assemblage is compared with similar faunas from the Upper Jurassic of Asturias, Spain and the Middle Jurassic Yorkshire Coast of England. The Portuguese record of Upper Jurassic dinosaur body fossils show close similarity to the track fauna from the Lourinha˜ Formation.

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Although the Late Jurassic of Portugal has provided abundant dinosaur fossils, material from the Early Cretaceous is scarce. This paper reports new cranial and postcranial material of the theropod dinosaur Baryonyx walkeri found in the Barremian (Papo Seco Formation) of Portugal. This specimen, found at Praia das Aguncheiras, Cabo Espichel, consists of a partial dentary, isolated teeth, pedal ungual, two calcanea, presacral and caudal vertebrae, fragmentary pubis, scapula, and rib fragments. It represents the most complete spinosaurid yet discovered in the Iberian Peninsula and the most complete dinosaur from the Early Cretaceous of Portugal. This specimen is confidently identified as a member of Baryonychinae due to the presence of conical teeth with flutes and denticles in a dentary rosette. The specimen ML1190 shares the following characteristics with Baryonyx walkeri: enamel surface with small (nearly vertical) wrinkles, variable denticle size along the carinae, 6–7 denticles per mm, wrinkles forming a 45 degree angle near the carinae, and tooth root longer than crown. In addition, dubious taxa based on teeth morphology such as Suchosaurus cultridens (Owen, 1840–1845), and Suchosaurus girardi (Sauvage 1897–98; Antunes & Mateus 2003) are discussed, based on comparisons with well-known material such as Baryonyx walkeri Charig & Milner, 1986. Suchosaurus cultridens and S. girardi are considered as nomina dubia due to the lack of diagnostic apomorphies, but both specimens are referred to Baryonychinae incertae sedis.

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The precursor of the North Atlantic existed between the North American and Iberian blocks from the earliest Jurassic Hettangian and has been ever expanding since. By the Kimmeridgian and Tithonian, when much of the Morrison Fm rocks were deposited, the proto-Atlantic was more than 300 km wide at 27° paleolatitude between North America and Iberia. Macrovertebrate paleontology reveals a unique story to the isolation of Iberia and instead suggest a paleogeographic land connection between North American and Iberia. Torvosaurus, Allosaurus, Ceratosaurus, Stegosaurus, Supersaurus and others have a distribution restricted to Morrison Formation in North America and Lourinhã Formation in Portugal. A novel paleogeographic model is here suggested: (1) around the Middle–Late Jurassic transition there is a major palaeoceanographic and palaeoclimatic reorganization, coincidental to a major eustatic sea-level drop and uplift associated with the Callovian– Oxfordian Atlantic Regressive Event; (2) creating an ephemeral land bridge presenting a temporary opportunity for terrestrial gateways likely across the Flemish Cap and Galician Bank land masses, allowing large dinosaurian taxa to cross the northern proto-Atlantic in both directions; (3) finally, a Callovian–Oxfordian faunal exchange around the 163 Ma, through latest Kimmeridgian at 152 Ma (the age of equivalent genera in both Morrison and Portugal), is was an interval that allowed speciation, but retaining generic similarity of vertebrates. This model is consistent with the chronology and taxonomy required for speciation of the Iberian and American forms, exemplified by the coeval sister-taxa pairs Torvosaurus tanneri and T. gurneyi, Allosaurus fragilis and A. europaeus, or Supersaurus vivianae and S. lourinhanensis. While some of the smaller animals in the fauna show Morrison/Portugal affinities, most from Iberia have European or even Asian affinities. The larger-bodied fauna are more closely related to Morrison than to mainland Europe (except for dacentrurine stegosaurs). The body size differences and affinities of taxa across paleogeography is comparable to what is observed today across the Wallace Line. Migration may have also occurred in both directions. The closest relative of Torvosaurus is likely the European Bathonian Megalosaurus, thus the presence of the genus in North America represents a European migration. On other hand, Allosaurus and Supersaurus origins are consistent with a North American origin, representing an westto-east migration.