Eocene (Ypresian-Lutetian) mammals from Cerro Pan de Azúcar (Gaiman, Chubut Province, Argentina)

CHORNOGUBSKY L; GOIN FJ; CIANCIO MR; PUERTA P; KRAUSE DW

Historical Biology

Taylor & Francis

Lugar: Londres; Año: 2023

0891-2963

The Gaiman region contains two notorious Cenozoic mammalian faunas, the richer and more diverse, early Miocene Bryn-Gwyn fauna, at the southern margin of the Chubut river, and the Paleogene Pan de Azúcar fauna, on its northern margin. The latter comes from Ypresian-Lutetian levels from the Las Flores Formation. In this work we present several new materials collected at the pink sandstone levels from the Las Flores Formation at the Cerro Pan de Azúcar and compare it with taxa present in other localities of similar age. The Metatheria taxa described here are 1) the Didelphimorphia Protodidelphis cf. P. mastodontoides and Guggenheimia glykeia sp. nov. (Protodidelphidae); Sternbergiidae indet (“Ameridelphia”, Sternbergiidae); 2) the Polydolopimorphia Pliodolops rothi and Pliodolops cf. P. kamektsen (Polydolopidae); 3) the Microbiotheria Eomicrobiotherium diluculum sp. nov. (Microbiotheriidae). On the other hand the Cingulata Dasypodidae is represented by the Astegotheriini Prostegotherium astrifer. This fauna shares more species with the localities from Paso del Sapo than with any other mid-Eocene locality and, at the generic level, it shares several taxa with the Itaboraian fauna from Sao José de Itaboraí. Finally, the faunal associations from Pan de Azúcar, Paso del Sapo, Cañadón Hondo, and Bajo de la Palangana could all represent local faunas from the Riochican SALMA.