NEW OCCURRENCES OF AMIIDAE (HALECOMORPHI: AMIIFORMES: VIDALAMIINAE) FROM THE BAURU GROUP (LATE CRETACEOUS, BRAZIL) AND COMMENTS ABOUT THEIR INCURSION IN FRESHWATER ENVIRONMENTS IN THE CRETACEOUS OF THE AMERICAS

Abstract

The Late Cretaceous continental deposits of the Bauru Group of Brazil have a rich vertebrate fossil fauna, but studies on the fossil fishes from the unit are scarce. This paper describes new occurrences of the Vidalamiinae subfamily of the bony fish group Amiidae (Halecomorphi: Amiiformes). The new occurrences are comprised by three isolated vertebral centra and three isolated teeth from the Marília and Adamantina formations, which were collected in Uberaba and Prata municipalities. The fossils described here not only expand the record of Vidalamiinae for the Bauru Group, but also clarify that the assignment of isolated teeth to this group may now be done with more certainty, which was not the case in many previous studies. Additionally, we also refer the described specimens tentatively to the Vidalamiini, which is the first assignment to this group and to the tribe level for any fish material from the Bauru Group. This study also offers an overview on the paleobiogeography of the Amiidae during the Late Cretaceous and an updated compilation of vidalamiine records during the Cretaceous, with a special focus on the freshwater records of this originally saltwater group. Finally, we also discuss the distribution of the tribes Vidalamiini and Calamopleurini during the Late Cretaceous, and the possibility that the North American and South American vidalamiines may have dispersed between the continents through a land connection.