Fossil Mysticeti from the Pleistocene of Santa Maria Island, Azores (Northeast Atlantic Ocean), and the prevalence of fossil cetaceans on oceanic islands

Abstract

Fossil remains of Cetacea are known globally from nearshore marine sediments along continental coastlines, but they are poorly known from volcanic oceanic island archipelagos. Here we report Pleistocene fossil cetacean material from late Neogene and Quaternary age outcrops on the Santa Maria Island of the Azores island archipelago in the North Atlantic Ocean. These remains consist of an isolated and highly worn fragment from the mandible of a mediumto large-sized baleen-bearing mysticete (i.e., Chaeomysticeti), which was exposed at the marine isotope stage 5 (sub-stage MIS 5e) level at Praia do Calhau, after Hurricane Gordon hit Santa Maria Island in August 2012. While this occurrence represents only the second description of Pleistocene cetaceans from volcanic oceanic islands, we predict that fossil cetaceans are likely underreported from oceanic islands, given their extant abundance and richness near oceanic island archipelagos today, whose geomorphology and oceanography provide important settings for the migration and life history patterns of living cetaceans. Sergio P. Avila. CIBIO, Centro de Investigacao em Biodiversidade e Recursos Geneticos, InBIO Laboratorio Associado, Polo dos Acores, Departamento de Biologia da Universidade dos Acores, Campus de Ponta Delgada, Apartado 1422, 9501-801 Ponta Delgada, Acores, Portugal; and MPB-Marine PalaeoBiogeography group, University of the Azores, Ponta Delgada, Portugal; and Faculdade de Ciencias da Universidade do Porto, Rua do Campo Alegre s/n, 4169-007 Porto, Portugal. avila@uac.pt Ricardo Cordeiro. CIBIO, Centro de Investigacao em Biodiversidade e Recursos Geneticos, InBIO Laboratorio Associado, Polo dos Acores, Departamento de Biologia da Universidade dos Acores, Campus de Ponta Delgada, Apartado 1422, 9501-801 Ponta Delgada, Acores, Portugal; and MPB-Marine PalaeoBiogeography group, University of the Azores, Ponta Delgada, Portugal. rjpcordeiro@gmail.com Ana R. Rodrigues. Departamento de Biologia da Universidade dos Acores, Campus de Ponta Delgada, Apartado 1422, 9501-801 Ponta Delgada, Acores, Portugal. arprodrigues.17@gmail.com Ana C. Rebelo. CIBIO, Centro de Investigacao em Biodiversidade e Recursos Geneticos, InBIO Laboratorio Associado, Polo dos Acores, Departamento de Biologia da Universidade dos Acores, Campus de Ponta Delgada, Apartado 1422, 9501-801 Ponta Delgada, Acores, Portugal; and MPB-Marine PalaeoBiogeography group, University of the Azores, Ponta Delgada, Portugal; and SMNS Staatliches Museum fur Naturkunde Stuttgart, Rosenstein 1, D-70191 Stuttgart, Germany. PE Article Number: 18.2.27A Copyright: Paleontological Society June 2015 Submission: 3 March 2015. Acceptance: 22 May 2015 Avila, Sergio P., Cordeiro, Ricardo, Rodrigues, Ana R., Rebelo, Ana C., Melo, Carlos, Madeira, P., and Pyenson , Nicholas D. 2015. Fossil Mysticeti from the Pleistocene of Santa Maria Island, Azores (Northeast Atlantic Ocean), and the prevalence of fossil cetaceans on oceanic islands. Palaeontologia Electronica 18.2.27A: 1-12 palaeo-electronica.org/content/2015/1225-oceanic-island-fossil-cetacean AVILA: OCEANIC-ISLAND FOSSIL CETACEAN acfurtadorebelo@gmail.com Carlos Melo. MPB-Marine PalaeoBiogeography group, University of the Azores, Ponta Delgada, Portugal; and Departamento de Geociencias da Universidade dos Acores, Campus de Ponta Delgada, 9501-801 Ponta Delgada, Acores, Portugal. casm.azores@gmail.com Patricia Madeira. CIBIO, Centro de Investigacao em Biodiversidade e Recursos Geneticos, InBIO Laboratorio Associado, Polo dos Acores, Departamento de Biologia da Universidade dos Acores, Campus de Ponta Delgada, Apartado 1422, 9501-801 Ponta Delgada, Acores, Portugal; and MPB-Marine PalaeoBiogeography group, University of the Azores, Ponta Delgada, Portugal. tamissa@hotmail.com Nicholas D. Pyenson. Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, NHB, MRC 121, PO Box 37012 10th & Constitution NW Washington, DC 20013-7012, USA. PyensonN@si.edu