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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 (Gaiman, Chubut Province, Argentina) and compare them with taxa present in other localities of similar age. The Metatheria taxa described here are 1) the 'Ameridelphia' Sternbergiidae indet; 2) the Didelphimorphia Protodidelphis cf. mastodontoides and Guggenheimia glykeia sp. nov. (Protodidelphidae); 3) the Polydolopimorphia Pliodolops rothi and Pliodolops cf. kamektsen (Polydolopidae); and 4) 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 those occurring in the localities from Paso del Sapo than with any other early – middle Eocene localities. However, 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 be, at least in part, synchronous, representing locally the Riochican SALMA, with an age spanning from 51 to 45 Ma (early Ypresian- early Lutetian). [ABSTRACT FROM AUTHOR]

Adapisoriculidae, a family of primitive eutherian, insectivore-like small mammals, is known from Europe, mainland Asia, India and Africa (Morocco, Namibia) but not thus far from the New World. Previous discoveries of this family in Africa were restricted to Morocco, but in 2019 a specimen was found in early to middle Eocene freshwater limestones at Black Crow, Namibia, thereby greatly extending the geographic range of the family well to the south of all other records of the group, even taking into account the northward drift of India since the early Palaeogene. A new genus and species is described and compared in detail with other members of the family as well as with other small-bodied eutherians and placentals. Its biogeography is discussed, but the limited amount of evidence available, allied with the huge geographic and temporal gaps in its distribution, does not yield a clear picture of where the family originated and when it dispersed to other parts of the Old World. [ABSTRACT FROM AUTHOR]