Cerro Redondo, c. 37 m above the "Banco Verde" : Danian, Argentina
collected by C. S. Williams, O. Garcia Fanjul.

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Reptilia - Crocodilia
Simpson 1935
Scutes, skeletal fragments, teeth
Mammalia - Panameriungulata - Notonychopidae
1 specimen
AMNH 28505 (holotype)
Simpson 1935 1 specimen
Lower molar
Mammalia - Xenungulata - Carodniidae
Gelfo et al. 2024
MLP-PV 90-II-12-121 - type
Mammalia - Sparassodonta - Borhyaenidae
Simpson 1935 1 specimen
Canine fragment
Mammalia - Polydolopidae
Seumadia yapa n. gen., n. sp. Simpson 1935
1 specimen
AMNH 28431 (holotype)
see common names

Geography
Country:Argentina State/province:Chubut
Coordinates: 45.3° South, 67.0° West (view map)
Paleocoordinates:46.3° South, 56.3° West (Wright 2013)
Basis of coordinate:estimated from map
Geographic resolution:outcrop
Time
Period: Paleogene Epoch: Paleocene
Stage: Danian 10 m.y. bin: Cenozoic 1
*Period:Early/Lower Tertiary *Epoch:Late/Upper Paleocene
*Local age/stage:Riochican
Key time interval: Danian Mammal zone:  Carodnian
Age range of interval: 66 - 61.66 m.y. ago
* legacy (obsolete) database fields
Stratigraphy
Geological group:Río Chico Formation:Peñas Coloradas
Stratigraphic resolution:group of beds
Stratigraphy comments: Generally regarded as middle or late Paleocene in age (e.g. Gelfo et al. 2009), but the fossil-bearing horizons (Carodnia zone) were dated as late Danian–Selandian by Clyde et al. (2014) and refined to late Danian by Krause et al. (2017)

Unit 'h', 36.5-38 metres above the base of the "Banco Negro Inferior."
Informal Carodnian zone, between Peligran and Itaboraian SALMA. Approximately correlative to the Selandian (Woodburne et al. 2014: fig. 1, J. Mammal Evol 21)
Lithology and environment
Primary lithology: sandstone
Secondary lithology: claystone
Environment:terrestrial indet.
Taphonomy
Modes of preservation:body
Size of fossils:macrofossils,mesofossils
Disassociated minor elements:some
Collection methods and comments
Collection excludes:all macrofossils
Collection methods:survey of museum collection
Reason for describing collection:taxonomic analysis
Museum repositories:AMNH
Collectors:C. S. Williams, O. Garcia Fanjul.
Metadata
Database number:13782
Authorizer:J. Alroy, P. Mannion, R. Butler Enterer:J. Wertheim, R. Butler, P. Mannion
Modifier:G. Varnham Research group:vertebrate
Created:2002-04-25 18:10:45 Last modified:2025-02-22 15:12:02
Access level:the public Released:2002-04-25 18:10:45
Creative Commons license:CC0
Reference information

Primary reference:
6147.5% 49100G. 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]

Secondary references:

89011 J. N. Gelfo, G. M. López, and M. Bond. 2024. New insights on the anatomy, paleobiology, and biostratigraphy of Xenungulata (Mammalia) from the Paleogene of South America. Palaeontologia Electronica 27(2):a30 [P. Mannion/P. Mannion]
57551 G. G. Simpson. 1935. Occurrence and relationships of the Rio Chico fauna of Patagonia. American Museum Novitates 818:1-21 [R. Butler/R. Butler]
57561 M. O. Woodburne, F. J. Goin, M. Bond, A. A. Carlini, J. N. Gelfo, G. M. López, A. Iglesias and A. N. Zimicz. 2014. Paleogene Land Mammal Faunas of South America; a Response to Global Climatic Changes and Indigenous Floral Diversity. Journal of Mammalian Evolution 21:1-73 [R. Butler/R. Butler]