Unexpected primitive rodents in the Quaternary of Argentina

This article describes the first fossils recorded in the Hernandarias Formation (Pleistocene) in Entre Ríos province (eastern Argentina). They are represented by three teeth assigned to the caviomorph rodents (Rodentia, Mammalia) Aenigmys diamantensis gen. et sp. nov. and Eumysops. To establish the...

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Detalles Bibliográficos
Autores: Vucetich, María Guiomar, Vieytes, Emma Carolina, Verzi, Diego Hector, Noriega, Jorge Ignacio, Tonni, Eduardo Pedro
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2005
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/80764
Acceso en línea:http://hdl.handle.net/11336/80764
Access Level:acceso abierto
Palabra clave:Argentina
Biodiversity
Biogeography
Entre Ríos
Phylogeny
Pleistocene
Rodentia
https://purl.org/becyt/ford/1.5
https://purl.org/becyt/ford/1
Descripción
Sumario:This article describes the first fossils recorded in the Hernandarias Formation (Pleistocene) in Entre Ríos province (eastern Argentina). They are represented by three teeth assigned to the caviomorph rodents (Rodentia, Mammalia) Aenigmys diamantensis gen. et sp. nov. and Eumysops. To establish the phylogenetic affinities of the two most enigmatic teeth, their enamel microstructure was studied. Aenigmys diamantensis is considered the most primitive taxon of a clade formed by Dinomyidae-Neoepiblemidae-Heptaxodontidae. Evidence of the close relationships among these families also is presented herein. The new fossils reinforce previous hypotheses about the survival of primitive Brazilian taxa after their extinction in the Pampas and Patagonia of southern South America. They also show that the diversity of caviomorph rodents during the Quaternary was greater than supposed and that an important Quaternary extinction, not previously detected, affected several lineages. With the available evidence, it is not possible to determine if these rodents indicate a warm pulse or a particular biogeographic situation in Entre Ríos.