CAR - upper Monte Leon Fm (Miocene of Argentina)

Where: Argentina (48.3° S, 67.7° W: paleocoordinates 49.0° S, 61.2° W)

• coordinate based on nearby landmark

• local area-level geographic resolution

When: Chenque Formation, Early/Lower Miocene (23.0 - 16.0 Ma)

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

• group of beds-level stratigraphic resolution

Environment/lithology: coastal; poorly lithified sandstone

• ENVIRONMENT: Environmental data not reported in text. Siliciclastic shallow marine assemblage.
• SPECIFIC LITHOLOGY: Sandstone. 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 71430: authorized by Austin Hendy, entered by Austin Hendy on 25.04.2007

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.
unclassified
  -
Gastropoda
 Heterostropha - Acteonidae
Actaeon argentinus Ihering 1907 snail
 Trochoidea - Trochidae
 Trochoidea - Tegulidae
 Trochoidea - Skeneidae
 Opisthobranchia - Retusidae
Volvulella cannada Ihering 1907 snail
 Opisthobranchia -
 Cerithioidea - Turritellidae
"Turritella" ambulacrum Sowerby 1846 turret shell
 Cerithioidea - Siliquariidae
Tenagodus cossmani Ihering 1907 snail
 Neotaenioglossa - Calyptraeidae
Crepidula gregaria slipper shell
 Epitonioidea - Epitoniidae
 Sorbeoconcha - Naticidae
""Polynices" sanatacrucensis" = Polinices, ""Polynices" secunda" = Polinices, ""Polynices" famula" = Polinices
""Polynices" sanatacrucensis" = Polinices moon snail
""Polynices" secunda" = Polinices moon snail
""Polynices" famula" = Polinices moon snail
 Sorbeoconcha - Newtoniellidae
 Neogastropoda - Buccinidae
Penion subrecta true whelk
 Neogastropoda - Cancellariidae
Sveltia major Ihering 1899 snail
 Neogastropoda - Mitridae
Austroimbricaria quemadensis Ihering 1897 mitre shell
 Neogastropoda - Terebridae
 Neogastropoda - Turridae
"Eoturris unifascialis" = Eopleurotoma, "Eoturris sanatacrucensis" = Eopleurotoma
"Eoturris unifascialis" = Eopleurotoma turrid
"Eoturris sanatacrucensis" = Eopleurotoma turrid
 Neogastropoda - Volutidae
 Neogastropoda - Muricidae
"Xymenella elegans" = Xymene murex snail
Trophon santacrucensis Ihering 1897 murex snail
"Urosalpinx" cossmanni Ortmann 1900 murex snail
Bivalvia
 Ostreida - Ostreidae
Crassostrea hatcheri Ihering 1899 oyster
 Arcida - Glycymerididae
 Cardiida - Cardiidae
Hedecardium philippi Ihering 1897 cockle
 Cardiida - Tellinidae
"? Tellinella patagonica" = Tellina (Tellinella) tellin clam
 Cardiida - Veneridae
Dosinia meridonalis Ihering 1897 venus clam
 Pholadida - Corbulidae
 Solenida - Solenidae
"Solen (Eosolen) crucis" = Solena (Eosolen)
"Solen (Eosolen) crucis" = Solena (Eosolen) clam
 Lucinida - Lucinidae
"Lucina" dalli Ihering 1907 clam
 Carditida - Carditidae