Where: Argentina (49.3° S, 67.7° W: paleocoordinates 51.0° S, 58.6° W)
• local area-level geographic resolution
When: San Julián Formation, Early/Lower Oligocene (33.9 - 28.4 Ma)
• STRATIGRAPHIC RELATIONS: From beds of the San Julián Fm, which unconformably overlies the Bahia Laura Group and is overlain by the Early Miocene Monte Leon Fm. THICKNESS: From multiple beds within formation that reaches a thickness of 100 m. AGE: Early Oligocene to Late Oligocene according to molluscan biostratigraphy. Assigned to the Early Oligocene based on the presence of Zygochlamys geminatus. STRATIGRAPHIC POSITION: From upper parts of the formation.
• group of beds-level stratigraphic resolution
Environment/lithology: coastal; unlithified, bioturbated sandstone and poorly lithified, sandy limestone
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 71402: authorized by Austin Hendy, entered by Austin Hendy on 24.04.2007
Creative Commons license: CC BY (attribution)
Taxonomic list
unclassified | |
Gastropoda | |
Solariella osborni snail | |
Cirsotrema rugulosa wentletrap | |
"Calyptraea" juliana slipper shell
"Calyptraea" pileus Lamarck 1822 slipper shell | |
Turritella patagonica turret shell | |
Struthiolarella ornata snail | |
Trophon santacrucensis Ihering 1897 murex snail | |
""Proscaphella" gracilior" = Miomelon gracilis
""Proscaphella" gracilior" = Miomelon gracilis Philippi 1887 volute | |
""Polynices" secunda" = Polinices, ""Polynices" subtenuis" = Polinices subtenuis
""Polynices" secunda" = Polinices moon snail
""Polynices" subtenuis" = Polinices subtenuis Ihering 1907 moon snail | |
Hipponix costata hoof shell | |
Bivalvia | |
"Cucullaea darwini" = Cucullaria darwini
"Cucullaea darwini" = Cucullaria darwini Philippi 1887 clam | |
"Arca (Barbatia) juliana" = Barbatia, Arca puntaensis
"Arca (Barbatia) juliana" = Barbatia clam
Arca puntaensis ark | |
Cucullaea (Monteleonia) marshalli Zinsmeister 1981 clam | |
Limopsis insolita Sowerby 1846 clam | |
Parinomya juliensis scallop
Parinomya patagonensis scallop | |
"Zygochlamys geminatus" = Zygochlamys geminata
"Zygochlamys geminatus" = Zygochlamys geminata Sowerby 1846 scallop | |
Crassostrea hatcheri Ihering 1899 oyster | |
"Aulacomya cf. ater" = Aulacomya atra, Modiolus ameghinoi
"Aulacomya cf. ater" = Aulacomya atra Molina 1782 mussel
Modiolus ameghinoi Ihering 1907 mussel | |
Pholadidea patagonica Philippi 1887 clam | |
Corbula juliana clam | |
Austrocallista iheringi, Pitar julianum, Dosinia laeviuscula, Dosinia burmeisteri, Dosinia meridonalis, "Chione" patagonica
Austrocallista iheringi Cossmann 1898 venus clam
Pitar julianum venus clam
Dosinia laeviuscula venus clam
Dosinia burmeisteri venus clam
Dosinia meridonalis Ihering 1897 venus clam
"Chione" patagonica Philippi 1887 venus clam | |
"Cardium" pisum Philippi 1887 cockle | |
Panopea sierrana clam | |
Pleuromeris sulcolunularis, Pleuromeris camaronesia, Pleuromeris cannada, "Fasciculicardia inaequalis" = Glyptoactis (Fasciculicardia)
Pleuromeris cannada clam
"Fasciculicardia inaequalis" = Glyptoactis (Fasciculicardia) clam | |
Crassatella kokeni clam
Spissatella longior clam | |