New records of hexanchiform sharks (Elasmobranchii: Neoselachii) from the Late Cretaceous of Antarctica with comments on previous reports and described taxa

• Published in: New Zealand Journal of Geology and Geophysics
• Main Authors: dos Santos, Rodolfo Otávio, Riff, Douglas, Rodriguez Amenabar, Cecilia, Rodriguez Cabral Ramos, Renato, Fernandes Rodrigues, Igor, Scheffler, Sandro Marcelo, Araújo Carvalho, Marcelo
• Format: Article in Journal/Newspaper
• Language: English
• Published: Royal Society of New Zealand
• Subjects: HEXANCHIFORMES; JAMES ROSS ISLAND; JAMES ROSS SUB-BASIN; LARSEN BASIN; LATE CRETACEOUS SHARKS; https://purl.org/becyt/ford/1.5; https://purl.org/becyt/ford/1; Antarctic; Antarctic Peninsula; Austral; Ross Island; Argentino; Argentina; Rodriguez; Pablo; Ramos; Hill Island; Snow Hill Island; Larsen Basin; Herbert Sound; Snow Hill; Antarc*; Antarctica; Dirección Nacional del Antártico; Instituto Antártico Argentino; James Ross Island
• Online Access: http://hdl.handle.net/11336/203404

Sharks are virtually absent from coastal Antarctica since the Late Eocene glaciations, but this group exhibited a notable austral diversity during the Cretaceous and Paleogene. Several species have already been described from the Aptian-Eocene successions of the Larsen Basin exposed in the James Ross Island area (northern Antarctic Peninsula) and the predominantly deep-water Hexanchiformes have a record that, although still rare, has been continually increased. Four species of this group are currently known from that basin: Notidanodon pectinatus, Xampylodon dentatus, Rolfodon thompsoni, and Rolfodon tatere. Such records are especially concentrated in the Gamma Member of the Snow Hill Island Formation (or Herbert Sound Member of Santa Marta Formation), on James Ross Island. Here we described four teeth assigned to X. dentatus and one identified as R. tatere from upper Campanian sections of James Ross Island, highlighting the nomenclatural changes that led to the definition of Xampylodon and Rolfodon. Some specimens of X. dentatus presented here are considerably more complete or represent teeth of different positions than most previous records. The material assigned to R. tatere represents the oldest record of this species in the world, extending its time range by more than 10 million years. Fil: dos Santos, Rodolfo Otávio. Universidade de Sao Paulo; Brasil Fil: Riff, Douglas. No especifíca; Fil: Rodriguez Amenabar, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; Argentina Fil: Rodriguez Cabral Ramos, Renato. Universidade Federal do Rio de Janeiro; Brasil Fil: Fernandes Rodrigues, Igor. Universidade Federal do Rio de ...