Diving in the Maastrichtian of Marambio (Seymour) Island: A new member of the Neoaves in the Cretaceous Antarctic avifauna

Abstract

A new genus and species of Cretaceous bird from Antarctica with implications for the early evolution of Neornithes is described here. The type specimen of Pujatopouli soberana gen. et sp. nov. (MLP-PV 08-XI-30-44), preserving part of the skull and postcranium, was recovered from Maastrichtian deposits of the López de Bertodano Formation on Marambio (Seymour) Island, James Ross Basin, West Antarctica. The phylogenetic relationships of Pujatopouli with other avian species, including all previously described Cretaceous birds from Antarctica, were assessed using two different datasets. The first, mainly composed of Mesozoic birds, places Pujatopouli within the crown group of birds (Neornithes), whereas the second, which includes a broad sampling of modern taxa, positions it within Neoaves, and closely related to the ‘core-waterbirds’ (Aequornithes). Besides, morphological evidence suggests that Pujatopouli was a foot-propelled diver with an ichthyophagous diet, living sympatrically with other neornithine birds along the Antarctic coast during the latest Cretaceous.