Valle de Traslasierra - Paso del Río Arriba Cliffs (Pliocene of Argentina)

Also known as Valle de Traslasierra - Paso del Río Arriba and Pedernara Cliffs

Where: Córdoba, Argentina (31.8° S, 65.0° W: paleocoordinates 31.9° S, 64.0° W)

• coordinate stated in text

• small collection-level geographic resolution

When: Brochero Formation, Chapadmalalan (4.0 - 3.0 Ma)

• It is very difficult to determine the age of deposition of the Brochero Formation of Traslasierra Valley. The fossil fauna of vertebrates recorded from the Brochero Formation allows us to propose 3 hypothesis regarding the age on the basis of the biochrons discussed above, the best hypothesis is that this assemblage may be Chapadmalalan in age. However more studies should be done.

•Cruz 2013: It corresponds to the biostratigraphic mammal assemblage 3) Nonotherium hennigie Propanochthus bullifer assemblage zone with type area and profile based on the Los Sauces river, Valle de Traslasierra, referred to the MontehermosaneChapadmalalan interval (Pliocene)

• group of beds-level stratigraphic resolution

Environment/lithology: "floodplain"; poorly lithified sandstone

• the facies associations here described suggest a fluvial paleoenvironment of meandering type where two major sub-environments are recognized: channels or channel belts (facies 1 to 4, Fig. 2) and vegetated floodplains (facies 5 and 6, Fig. 2). The meandering river systems con- sist of a single high sinuosity channel (with point bars or bars spurs) and floodplain deposits with fine sedimentation and overflow lobes and channels.
• Sands with cross bedding (St) facies: they are medium-scale cross strata composed of layers offine sand with sigmoidal geometry and layers ofsand with trough cross-bedding, both forming sets ofaverage thick- ness varying between 10 and 15 cm (not more than 30 cm), separated by millimetric to centimetric layers ofsilts and clays arranged parallel to the surface oflateral accretion, interpreted as deposits of lateral accretion bars;

Size classes: macrofossils, mesofossils

Collected by Castellanos in 1936, 1942, 1944 etc.

• Castellanos (1942, 1944) described from Valle de Traslasierra (Fig. 1) at least seven sites where outcropping sediments were assigned to his BBrocherense,^ but only three with fossils (Los Chiflones stream, Paso del Río Arriba Cliffs, and Heredia Cliffs, see point 2, 4, and 5, respectively in Fig. 1). All these cliffs have been identified in different field trips from 2009 to 2016.

Primary reference: L. E. Cruz, J. C. Fernicola, and C. A. Carignano. 2018. New Vertebrates of the Brochero Formation (Córdoba, Argentina): A Review of the Pliocene of Central Argentina. Journal of Mammalian Evolution 25:315-326 [P. Mannion/M. Kouvari]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 197905: authorized by Philip Mannion, entered by Miranta Kouvari on 28.11.2018

Creative Commons license: CC BY (attribution)

Taxonomic list

• Finally, materials collected in the Valle de Traslasierra are housed in the MUFyCA in Rosario
Amphibia
 Salientia - Bufonidae
Rhinella cf. spinulosa toad
MCNC-PV 308
Rhinella cf. arenarum Hensel 1867 toad
MCNC-PV 307
Reptilia
 Squamata - Colubridae
Colubridae indet. Oppel 1811 colubrid snake
MCNC-PV 295
 Squamata - Teiidae
Teius sp. Merrem 1820 Four-toed tegus
MCNC-PV-291
 Squamata - Tropiduridae
? Liolaemus sp. Wiegmann 1834 Tree iguanas
MCNC-PV 292, MCNC-PV 293
 Squamata - Iguanidae
Iguanidae indet. Oppel 1811 squamates
MCNC-PV-294
Mammalia
 Rodentia - Echimyidae
Echimyidae indet. Gray 1825 spiny rat
MCNC-PV 300
 Rodentia - Cricetidae
Chukimys favaloroi Barbiere et al. 2016 mouse
Holotype: MCNC-PV-298, Paratype: MCNC- PV-299