Where: Chubut, Argentina (45.1° S, 68.1° W: paleocoordinates 47.6° S, 58.1° W)

• coordinate based on nearby landmark

• local area-level geographic resolution

When: Casamayor Formation, Casamayoran (55.8 - 48.0 Ma)

• Lowest fossil horizon, Casamayor Formation

Environment/lithology: terrestrial; claystone

Size class: macrofossils

Primary reference: G. G. Simpson. 1935. Descriptions of the oldest known South American mammals, from the Rio Chico Formation. American Museum Novitates 793:1-25 [J. Alroy/J. Wertheim/J. Wertheim] more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 13779: authorized by John Alroy, entered by Jill Wertheim on 25.04.2002

Creative Commons license: CC BY-NC-ND (attribution-noncommercial-no derivatives)