UCMP V-4528 Upper Red Bed (Miocene of Colombia)

Also known as Upper Red Bed

Where: Huila, Colombia (3.2° N, 75.2° W: paleocoordinates 2.6° N, 72.6° W)

• coordinate estimated from map

• small collection-level geographic resolution

When: Villavieja Formation (Honda Group), Laventan (13.8 - 11.8 Ma)

• Upper Red Beds - El Cardón Red Beds

Environment/lithology: fluvial; claystone and mudstone

• "This unit is easily differentiated from others as it is composed of rather thin layers (20 to 30 centimeter thick) of even-bedded, dull-red claystone with numerous thin interbeds of gray claystone. The basal and uppermost layers of the Upper Red Bed, like those of the Lower Red Bed, are not red. The most significant mineralogical feature displayed by the Upper Red Bed is the presence of bentonite, which constitutes some 35 per cent of the material composing the beds. Montmorillonite is evidently the constituent mineral, as the clay swells and slumps when placed in water. Quartz is present as extremely small rounded grains and constitutes about 60 per cent of the detrital fraction. Muscovite is also present. The red limonite stain is not soluble in cold hydrochloric acid but is completely soluble in hot hydrochloric acid. After the stain is dissolved, the clay residue is the same greenish-gray color as the upper and lower beds of this unit, indicating that all but the middle layers were probably leached before or shortly after deposition. The presence of bentonite is significant, for only in the unit below the Upper Red Bed are there any traces of volcanic materials." Lithological description taken from Fields (1959): Geology of the La Venta Badlands Colombia, South America. Vol 32, 405-444.

Size classes: macrofossils, mesofossils, microfossils

Primary reference: R. A. Stirton. 1953. A new genus of interatheres from the Miocene of Colombia. California University Department of Geological Sciences B 29(6):265-347 [C. Jaramillo/M. Vallejo/A. Cardenas ]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 187114: authorized by Andrés Cardenas, entered by Laura Mora-Rojas on 14.07.2017

Creative Commons license: CC BY (attribution)

Taxonomic list

Mammalia
 Notoungulata - Interatheriidae
Miocochilius anomopodus Stirton 1953 notoungulate
UCMP 38056, 38848, 38858, 40916
 Rodentia - Dinomyidae
Scleromys colombianus1 Fields 1957 caviomorph
UCMP 38900, 38960
Scleromys schurmanni1 Stehlin 1940 caviomorph
Specimen n° UCMP 38901, 38902
"Olenopsis aequatorialis" = Drytomomys aequatorialis1 Anthony 1922 caviomorph
UCMP 40623
 Astrapotheria - Astrapotheriidae
Xenastrapotherium kraglievichi5 Cabrera 1929 placental
Specimen nº UCMP 38922
Granastrapotherium snorki4 Johnson and Madden 1997 placental
UCMP 38843, 38907, 38931
 Xenarthra - Myrmecophagidae
Neotamandua borealis2 Hirschfeld 1976 edentate
UCMP 39817
 Xenarthra - Megatheriidae
Megatheriinae indet.3 Gill 1872 edentate
Gill, 1872. UCMP 38908
 Xenarthra - Mylodontidae
Mylodontidae indet.3 Savage 1951 edentate
Scelidothere, UCMP 38893
Pseudoprepotherium confusum3 Hirschfeld 1985 edentate
Hirschfeld 1985, UCMP 38919, 38914, 38881, 38853, 38854