Ray-finned fishes (Actinopterygii) from the Upper Jurassic (Oxfordian) of the Atacama Desert, Northern Chile

Abstract

This contribution presents novel records of ray-finned fishes from the Oxfordian of Cerritos Bayos, northern Chile. This includes a Pachycormiformes diversity represented by macropredatory forms (aff. Hypsocormus sp. and a still indeterminate form) and by suspension-feeding forms (Leedsichthys sp). The assemblage also includes the first Upper Jurassic local record of a Lepisosteidae, the latter being the oldest known to date in Gondwana. This diversity is complemented by new material of the lepidotid genus Scheenstia. The ray-finned fish assemblage from the Oxfordian of Cerritos Bayos is dominated by Lepisosteiformes and Pachycormiformes, complementing previous local coeval records from El Profeta Formation (ca. 250 km south from the localities here studied), mostly comprised by small Teleostei (e.g., Protoclupea chilensis, Varasichthys ariasi, Chongichthys dentatus, among others), indeterminate Pachycormiformes and Pycnodontiformes (Gyrodus sp.). The new records extend the known actinopterygian diversity from the Upper Jurassic of southeastern Panthalassa.