Early Pliocene heteropods and pteropods (Mollusca, Gastropoda) from SantaMaria Island (Azores, Portugal): systematics and biostratigraphic implications
Authors
Arie W. Janssen
Nationaal Natuurhistorisch Museum Naturalis (Palaeontology Department), P.O. Box 9517, 2300 RA Leiden, The Netherlands; currently: 12, Triq tal’Hamrija, Xewkija XWK 9033, Gozo
Andreas Kroh
2Natural History Museum Vienna, Department of Geology & Palaeontology, Burgring 7, 1010 Vienna
Sergio P. Avila
3MPB – Marine Palaeobiogeography Working Group of the University of the Azores, Departamento de Biologia, Universidade dos Açores, Rua da Mãe de Deus, Apartado 1422, 9501 - 801 Ponta Delgada, Açores, Portugal;
Centro do IMAR da Universidade dos Açores, 9901-862 Horta, Azores
Aholoplanktonic mollusc assemblage from Neogene sediments of theAzorean island Santa Maria is described and analysed to determine the age of the sediments. Sixteen taxa are documented (three heteropods, thirteen pteropods), fourteen of which are new records for the fossil fauna of SantaMaria Island. The composition of the heteropod and pteropod assemblage indicates a Zanclean age, which contrasts with earlier age assignments to the Early, Middle or LateMiocene based on benthicmolluscs, but is in good agreement withmore recent data based on foraminiferal and geochemical evidence.The pteropod Cavolinia marginata (BRONN, 1862) is re-described based on abundant topotypic material and a neotype is designated. The species Cavolinia vendryesiana (GUPPY, 1873) is considered to be a junior subjective synonym of C. marginata. The temporal range of the pteropod Limacina trochiformis (D’ORBIGNY, 1836) is extendedto the Zanclean.
