title: Ichnological evidence of Megalosaurid Dinosaurs Crossing Middle Jurassic Tidal Flats.
abstract: A new dinosaur tracksite in the Vale de Meios quarry (Serra de Aire Formation, Bathonian, Portugal)preserves more than 700 theropod tracks. They are organized in at least 80 unidirectional trackways arranged in a bimodal orientation pattern (W/NW and E/SE). Quantitative and qualitative comparisons reveal that the large tridactyl, elongated and asymmetric tracks resemble the typical Late Jurassic-Early Cretaceous Megalosauripus ichnogenus in all morphometric parameters. Few of the numerous tracks are preserved as elite tracks while the rest are preserved as different gradients of modified true tracks according to water content, erosive factors, radial fractures and internal overtrack formations. Taphonomical determinations are consistent with paleoenvironmental observations that indicate an inter-tidal flat located at the margin of a coastal barrier. The Megalosauripus tracks represent the oldest occurrence of this ichnotaxon and are attributed to large megalosaurid dinosaurs. Their occurrence in Vale de Meios tidal flat represents the unique paleoethological evidence of megalosaurids moving towards the lagoon, most likley during the low tide periods with feeding purposes.
authors.affiliation: Mesozoic Research Group, Institut Català de Paleontologia 'Miquel Crusafont', C/ Escola Industrial 23, 08201 Sabadell, Catalonia, Spain.
authors.forename: Novella L
authors.initials: NL
authors.lastname: Razzolini
authors.affiliation: Universitat Autonoma de Barcelona, Facultat de Ciències (Geologia), 08193, Bellaterra (Spain).
authors.forename: Oriol
authors.initials: O
authors.lastname: Oms
authors.affiliation: Bayerische Staatssammlung für Paläontologie und Geologie and GeoBioCenter, Ludwig-Maximilians-Universität, Richard-Wagner-Str. 10, 80333 Munich, Germany.
authors.forename: Diego
authors.initials: D
authors.lastname: Castanera
authors.affiliation: Mesozoic Research Group, Institut Català de Paleontologia 'Miquel Crusafont', C/ Escola Industrial 23, 08201 Sabadell, Catalonia, Spain.|Museu de la Conca Dellà, carrer del Museu, 4, 25650, Catalonia, Spain.
authors.forename: Bernat
authors.initials: B
authors.lastname: Vila
authors.affiliation: Museu Nacional de História Natural e da Ciência - Universidade de Lisboa, Rua da Escola Politécnica, 58, 1250-102 Lisboa, Portugal.
authors.forename: Vanda Faria Dos
authors.initials: VF
authors.lastname: Santos
authors.affiliation: Mesozoic Research Group, Institut Català de Paleontologia 'Miquel Crusafont', C/ Escola Industrial 23, 08201 Sabadell, Catalonia, Spain.|Museu de la Conca Dellà, carrer del Museu, 4, 25650, Catalonia, Spain.
authors.forename: Àngel
authors.initials: À
authors.lastname: Galobart
mesh_terms: D000818:Animals; D025061:Dinosaurs / Q000502:physiology*; D005580:Fossils; D005684:Gait; D010163:Paleontology; D011174:Portugal