A Sperm Whale (Cetacea: PhyseteroIdea) from the Paraná Formation (Late Miocene) of Entre Ríos, Argentina. Environment and taphonomy

LEANDRO M. PÉREZ; ALBERTO L. CIONE; MARIO COZZUOL; AUGUSTO N. VARELA

AMEGHINIANA

ASOCIACION PALEONTOLOGICA ARGENTINA

Lugar: La Plata; Año: 2011 vol. 2011 p. 648 - 654

0002-7014

Sperm whales (Physeteroidea) are known since the late Oligocene. They became very diverse during the middle and late Miocene (Bianucci and Landini, 2006). They are currently represented by only three species. Sperm whales have been reported in Argentina from the early Miocene Gaiman Formation [Diaphorocetus pouchetti Moreno, 1892, and Idiorophus patagonicus (Lydekker, 1893)], Gran Bajo del Gualicho Formation (Preaulophyseter gualichensis Caviglia and Jorge, 1980), the late Miocene Barranca Final Formation (?Aulophyseter? rionegrensis Gondar, 1975), and the late Miocene Paraná Formation (cf. Aulophyseter sp. by Agnolín and Lucero, 2004). Unfortunately, there are very few published Miocene cetaceans with good stratigraphic and geographic provenance from central-eastern Argentina (e.g., Balaenopteridae indet.; Noriega et al., 2007). Recently, one of us (LMP) found a piece of carbonate rock with an embedded physeteroid tooth coming from upper levels of the Paraná Formation. The material was collected in the quarry known as ?Cantera del Puerto Viejo? (GPS: 31°42′36″ S?60°33′10″W), close to the city of Paraná, Entre Ríos Province (Fig. 1). In this note, we describe the tooth, discuss the identification of another physeteroid tooth from the same stratigraphic unit, and compare them with different sperm whales. Additionally, we analyze the sedimentology and comment on the associated fauna and the taphonomic processes that acted on the fossil and the paleoenvironment.