A Late Jurassic Ginglymodians and Pycnodontiformes from Torres Vedras, Portugal.

Abstract

For the last 20 to 25 years, Torres Vedras has been the scene of a crucial, vast and diversenumber of fossil vertebrate occurrences. Bony fish are part of this important collection. Here we present a set of 64 Pycnodontiformes indet. specimens, comprising isolated and partially articulated vomerine and prearticular teeth, collected on the surface of the marine deposits of the top of Praia Azul Member, Lourinhã Formation, dating between upper Kimmeridgian- lower Tithonian. Additionally, 29 non- to partially articulated and sediment- covered body scale specimens, attributed to cf. Ginglymodi, were collected on a silt layer in Ulsa beach, near the Cambelas locality, from the Freixial Formation, dating from middle-upper Tithonian, Upper Jurassic. After CT Scan data analysis, the processing of 3D tomographic images of the latter set of specimens revealed the presence of body fragments within the matrix and, more importantly, scales with a very diagnostic peg, for transversal articulation, related to peg-and-socket articulation, typical of ginglymodian neopterygians. Therefore, with this study, based on the external 3D processing on these particular scale specimens, the presence of cf. Ginglymodi in the Upper Jurassic of Torres Vedras is hereby consolidated.