The species of genus Chasicotatus Scillato-Yané (Eutatini, Dasypodidae)

  • Gustavo Juan Scillato-Yané Consejo Nacional de Investigaciones Científicas y Técnicas. División Paleontología de Vertebrados, Museo de La Plata, Paseo del Bosque s/n, 1900, La Plata, Argentina.
  • Cecilia Mariana Krmpotic Consejo Nacional de Investigaciones Científicas y Técnicas. División Paleontología de Vertebrados, Museo de La Plata, Paseo del Bosque s/n, 1900, La Plata, Argentina.
  • Graciela Irene Esteban Instituto Superior de Correlación Geológica (INSUGEO), Facultad de Ciencias Naturales e Instituto Miguel Lillo, Miguel Lillo 205, 4000, San Miguel de Tucumán, Argentina.
Keywords: Xenarthra, Eutatini, Chasicotatus, systematic, palaeohistology, Arroyo Chasicó Formation, Argentina.

Abstract

Chasicotatus was originally described as a monotypic genus based on Chasicotatus ameghinoi Scillato-Yané, 1979, from the upper member of Arroyo Chasicó Formation (Las Barrancas Member, late Chasicoan). An additional species, Chasicotatus peiranoi, was erected by Esteban and Nasif (1996). This work presents the description of two new species previously recognized but never published by Scillato- Yané (1982), with a study and description of the osteoderm’s internal structure from three of four species of the genus. On this basis, the genus is revised and expanded diagnoses are provided for the previously known taxa, so that the species are clearly differentiated by internal and external osteodermal features. The geographical distribution of the species of genus Chasicotatus supports advanced palaeoenvironmental hypotheses previously proposed by different authors.

Published
2017-12-13
Section
Articles