The oldest plesiosaur (Reptilia, Sauropterygia) from Antarctica

• Published in: Polar Research
• Main Authors: Alexander Wilhelm Armin Kellner, Tiago Rodrigues Simões, Douglas Riff, Orlando Grillo, Pedro Romano, Helder de Paula, Renato Ramos, Marcelo Carvalho, Juliana Sayão, Gustavo Oliveira, Taissa Rodrigues
• Format: Article in Journal/Newspaper
• Language: English
• Published: Norwegian Polar Institute 2011
• Subjects: James Ross Island; Antarctica; plesiosauria; Late Cretaceous; Museu Nacional; oldest; geo; Antarctic; Antarctic Peninsula; Hill Island; Lachman; Lachman Crags; Ross Island; Snow Hill; Snow Hill Island; The Antarctic; Antarc*; Polar Research
• Online Access: https://doi.org/10.3402/polar.v30i0.7265; https://doaj.org/article/4551190776d14f62ab1afea3642a3642

Antarctic plesiosaurs are known from the Upper Cretaceous López de Bertodano and Snow Hill Island formations (Campanian to upper Maastrichtian), which crop out within the James Ross Basin region of the Antarctic Peninsula. Here we describe the first plesiosaur fossils from the Lachman Crags Member of the Santa Marta Formation, north-western James Ross Island. This material constitutes the stratigraphically oldest plesiosaur occurrence presently known from Antarctica, extending the occurrence of plesiosaurians in this continent back to Santonian times (86.3–83.5 Mya). Furthermore, MN 7163-V represents the first plesiosaur from this region not referable to the Elasmosauridae nor Aristonectes, indicating a greater diversity of this group of aquatic reptiles in Antarctica than previously suspected.