Sciuridae (Rodentia, Mammalia) from the Late Miocene of Venta del Moro (Cabriel Basin, Spain): biostratigraphical, phylogenetic and palaeoecological inferences

Abstract

Fossil squirrels are relatively abundant in Aragonian and Ramblian assemblages, but very scarce in the Late Turolian and Ruscinian of the Iberian Peninsula. Until now, the locality of Venta del Moro has yielded over 4500 micromammal dental remains, but just nine of them are sciurids. In this assemblage, we have identified the taxa Pliopetaurista pliocaenica, Heteroxerus cf. mariatheresae and Atlantoxerus cf. margaritae. This is the first co-occurrence of the genera Pliopetaurista, Heteroxerus and Atlantoxerus in the same locality, being also one of the oldest records of P. pliocaenica, the oldest record of a form that could be related to A. margaritae, and the youngest record of the genus Heteroxerus. In addition, we hypothesize about the phylogeny of Pliopetaurista in the light of recent discoveries. Finally, the presence of the genera Heteroxerus and Atlantoxerus suggests an open environment and relatively dry environmental conditions, while Pliopetaurista is purportedly a flying squirrel, dweller of forested habitats and wet climates. Based on this, we infer an open environment of grassland type, bordered by forested habitats, agreeing with the conditions supposed for Venta del Moro according to its macromammal and floral assemblages.

Keywords:

• Sciuridae
• biostratigraphy
• phylogeny
• palaeoecology
• Spain

Acknowledgments

The field work in Venta del Moro was supported, from 1995 on, by the Conselleria de Cultura of the Valencian Government with the permission of the Ministerio de Fomento and the Company ADIF, of the Spanish Government. We thank the efficient work of the technicians of the SCSIE of the UV, P. Gómez, E. Navarro and A.J. Ibáñez. This investigation was carried out thanks to the Prometeo Project of the Secretariat for Higher Education, Science, Technology and Innovation from Ecuador. This investigation has been funded through the project GV06/304 of the Conselleria d’Empresa, Universitat i Ciència ‘Estudio paleoambiental del tránsito Mioceno-Plioceno en facies continentales en la Comunidad Valenciana (Cuencas del Cabriel y de Alcoy)’ and the Project CGL2015-68,333-P (MINECO/FEDER, UE). We thank the comments and suggestions by the reviewers Dr. Antonio García-Alix and Dr. Gloria Cuenca, and editor Dr. Gareth Dyke.