Alto Río Cisnes (Miocene of Chile)

Where: Aisén, Chile (44.6° S, 71.2° W: paleocoordinates 45.2° S, 66.3° W)

• coordinate stated in text

• local area-level geographic resolution

When: Friasian mammal zone, Río Frias Formation, Friasian (16.3 - 15.5 Ma)

• Vera, et al. 2018: Two 40Ar/39Ar dates of “about 16.5 Ma” (Flynn & Swisher 1995, p. 325) and 14.83 ± 0.17 Ma (de la Cruz & Cort?es 2011) indicate a Burdigalian?Langhian age.

• formation-level stratigraphic resolution

Environment/lithology: fluvial; tuff and fine-grained, medium, brown, white sandstone

• The sediments of the Río Frías Formation were deposited in a high energy continental fluvial environment.
• This unit consists of dacitic and rhyolitic tuffs, tuffites, siltstones, and fine to medium sands which are principally white, light brown and/or orange in color. The sediments are generally well stratified, poorly consolidated and horizontal to subhorizontal, dipping ca. 30 to the north.

•Vera, et al. 2018: continental pyroclastic sequence belonging to the R?ıoFr?ıas Formation at Alto R?ıo Cisnes, Chile (Fig. 1). This unit is characterized mainly by tuffs, tuffites and palaeosols (Dal Mol?ın 1998; Escosteguy et al. 2003; de la Cruz & Cort?es 2011; Bostelmann et al. 2012 and references cited therein)

Size class: macrofossils

Reposited in the MNHN

• Specimens from Vera, et al. 2018 come from Roth's collection

Primary reference: L. G. Marshall. 1990. Fossil Marsupialia from the type Friasian Land Mammal Age (Miocene), Alto Rio Cisnes, Aisen, Chile. Revista Geológica de Chile 17(1):19-55 [C. Jaramillo/J. Carrillo/J. Carrillo]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 139845: authorized by Carlos Jaramillo, entered by Juan Carrillo on 19.02.2013, edited by Miranta Kouvari and Grace Varnham

Creative Commons license: CC BY (attribution)

Taxonomic list

Mammalia
 Primates -
 Rodentia - Chinchillidae
Prolagostomus sp.1 Ameghino 1887 chinchilid
 Rodentia - Dinomyidae
? Simplimus sp.1 Ameghino 1904 caviomorph
 Rodentia - Neoepiblemidae
Perimys sp.1 Ameghino 1887 caviomorph
 Rodentia -
Acarechimys sp.1 Patterson 1965 caviomorph
Protacaremys sp.1 Ameghino 1902 caviomorph
Neoreomys australis1 Ameghino 1887 caviomorph
 Cingulata - Propalaehoplophoridae
"Eucinepeltus cf. petesatus" = Encinepeltus petesatus1
"Eucinepeltus cf. petesatus" = Encinepeltus petesatus1 Ameghino 1891 edentate
 Notoungulata - Toxodontidae
Palyeidodon obtusum1 Roth 1898 notoungulate
 Notoungulata - Hegetotheriidae
Pachyrukhos sp.1 Ameghino 1885 notoungulate
 Notoungulata - Interatheriidae
Protypotherium "sp. nov?"3 Ameghino 1882 notoungulate
MLP12-2876a (Kraglievich in 1930 thought it's Protypotherium sp.)
"Protypotherium cf. endiadys" = Protypotherium praerutilum3 Ameghino 1887 notoungulate
MLP12-2880a (Kraglievich in 1930 thought it's Protypotherium sp.)
Protypotherium australe1 Moreno 1882 notoungulate
 Sparassodonta -
Sipalocyon gracilis Ameghino 1887 metatherian
Cladosictis patagonica Ameghino 1887 metatherian
 Sparassodonta - Borhyaenidae
Prothylacynus patagonicus Ameghino 1891 metatherian
Borhyaena tuberata Ameghino 1887 metatherian
 Paucituberculata - Abderitidae
Abderites meridionalis Ameghino 1887 marsupial
Pitheculites rothi n. sp. Marshall 1990 marsupial
 Paucituberculata - Pichipilidae
Pichipilus halleuxi n. sp. Marshall 1990 marsupial
 Paucituberculata - Palaeothentidae
Parabderites bicrispatus Ameghino 1902 marsupial
Palaeothentes intermedius Ameghino 1887 marsupial
Palaeothentes minutus Ameghino 1887 marsupial
Palaeothentes lemoinei Ameghino 1887 marsupial
 Microbiotheria - Microbiotheriidae
Microbiotherium tehuelchum Ameghino 1887 marsupial