MAN - middle Monte Leon Fm (Miocene of Argentina)

Where: Argentina (50.9° S, 71.7° W: paleocoordinates 51.7° S, 65.0° W)

• coordinate based on nearby landmark

• local area-level geographic resolution

When: Monte Leon Fm Formation, Early/Lower Miocene (23.0 - 16.0 Ma)

• STRATIGRAPHIC RELATIONS: From middle beds of the Monte Leon Fm. THICKNESS: From multiple beds within part of formation of around 100 m. AGE: Early Miocene according to molluscan biostratigraphy. Assigned to the early Early Miocene based on the the recognition of the upper RSP assemblage. STRATIGRAPHIC POSITION: From middle part of the formation.

• group of beds-level stratigraphic resolution

Environment/lithology: coastal; poorly lithified, tuffaceous sandstone and poorly lithified, sandy limestone

• ENVIRONMENT: Environmental data not reported in text. Siliciclastic shallow marine assemblage.
• SPECIFIC LITHOLOGY: Sandstone, tuffaceous sandstone, and sandy limestone. LITHIFICATION: Poorly-lithified on the basis of figured specimens.

Size class: macrofossils

Collection methods: COLLECTOR: List includes both new collections by the author, and examination of museum and previously reported taxa. REPOSITORY: Museo Argentino de Ciencias Naturales Bernadino Rivadavia, Buenos Aires, Argentina.

Primary reference: C. J. del Rio. 2004. Tertiary Marine Molluscan Assemblages of Eastern Patagonia (Argentina): A Biostratigraphic Analysis. Journal of Paleontology 78(6):1097-1122 [L. Ivany/P. Wall/P. Wall]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 71541: authorized by Austin Hendy, entered by Austin Hendy on 28.04.2007

Creative Commons license: CC BY (attribution)

Taxonomic list

• COVERAGE: Exhaustive for bivalvia and gastropoda. NOMENCLATURE: Not an authoritaive publication, but providing revised generic placement for many previously reported antiquated names.
Gastropoda
 Cerithioidea - Turritellidae
"Turritella" ambulacrum Sowerby 1846 turret shell
 Epitonioidea - Epitoniidae
Bivalvia
 Nuculida -
 Carditida - Crassatellidae
 Lucinida - Lucinidae
 Cardiida - Veneridae
Austrocallista iheringi Cossmann 1898 venus clam
 Arcida - Cucullaeidae
 Arcida - Limopsidae
Limopsis insolita Sowerby 1846 clam
 Ostreida - Ostreidae
Crassostrea hatcheri Ihering 1899 oyster