Late Campanian-Early Maastrichtian Vertebrates From The James Ross Basin, West Antarctica: Updated Synthesis, Biostratigraphy, And Paleobiogeography

• Published in: Anais da Academia Brasileira de Ciências
• Main Authors: MARCELO A. REGUERO, ZULMA GASPARINI, EDUARDO B. OLIVERO, RODOLFO A. CORIA, MARTA S. FERNÁNDEZ, JOSÉ P. O´GORMAN, SOLEDAD GOUIRIC-CAVALLI, CAROLINA ACOSTA HOSPITALECHE, PAULA BONA, ARI IGLESIAS, JAVIER N. GELFO, MARÍA E. RAFFI, JUAN JOSÉ MOLY, SERGIO N. SANTILLANA, MAGALÍ CÁRDENAS
• Format: Article in Journal/Newspaper
• Language: English
• Published: Academia Brasileira de Ciências 2022
• Subjects: Antarctic Peninsula; Late Cretaceous; NG Sequence; Snow Hill Island Formation; Science; Q; Antarctic; The Antarctic; West Antarctica; Hill Island; Snow Hill Island; Cape Lamb; Snow Hill; Antarc*; Antarctica
• Online Access: https://doi.org/10.1590/0001-3765202220211142; https://doaj.org/article/38b5f3199b944877929d26354afd4954

Abstract The Snow Hill Island Formation (SHIF; late Campanian – early Maastrichtian) crops out in the northeast of the Antarctic Peninsula and constitutes the basal part of the late Campanian-early Maastrichtian sedimentary succession of the James Ross Basin (NG Sequence). Its major exposures occur at the James Ross and Vega islands. Several fossil-bearing localities have been identified in the SHIF providing a valuable fauna of invertebrates and vertebrates, and flora. Our study focuses on the vertebrate fauna recovered at Gamma and Cape Lamb members of the SHIF. The marine vertebrate assemblages include chondrichthyans, actinopterygians, and marine reptiles (elasmosaurid plesiosaurs and mosasaurs). A diverse terrestrial vertebrate assemblage has been reported being characterized by dinosaurs (sauropod, elasmarian ornithopods, nodosaurid ankylosaur, and a paravian theropod), pterosaurs and birds. Most SHIF dinosaurs share close affinities with penecontemporaneous taxa from southern South America, indicating that at least some continental vertebrates could disperse between southern South America and Antarctica during the Late Cretaceous. The Snow Hill Island Formation provides the most diverse Late Cretaceous marine and continental faunas from Antarctica. The present study summarizes previous and new vertebrate findings with the best actualized stratigraphical framework, providing a more complete fauna association and analyzing further perspectives.