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 | |
Bivalvia | |
Modiolus ameghinoi, "Aulacomya cf. ater" = Aulacomya atra
Modiolus ameghinoi Ihering 1907 mussel
"Aulacomya cf. ater" = Aulacomya atra Molina 1782 mussel | |
"Cucullaea darwini" = Cucullaria darwini
"Cucullaea darwini" = Cucullaria darwini Philippi 1887 clam | |
Cucullaea (Monteleonia) marshalli Zinsmeister 1981 clam | |
"Arca (Barbatia) juliana" = Barbatia, Arca puntaensis
"Arca (Barbatia) juliana" = Barbatia clam
Arca puntaensis ark | |
Limopsis insolita Sowerby 1846 clam | |
Crassostrea hatcheri Ihering 1899 oyster | |
"Zygochlamys geminatus" = Zygochlamys geminata
"Zygochlamys geminatus" = Zygochlamys geminata Sowerby 1846 scallop | |
Parinomya juliensis scallop
Parinomya patagonensis scallop | |
Crassatella kokeni clam
Spissatella longior clam | |
"Fasciculicardia inaequalis" = Glyptoactis (Fasciculicardia), Pleuromeris sulcolunularis, Pleuromeris camaronesia, Pleuromeris cannada
"Fasciculicardia inaequalis" = Glyptoactis (Fasciculicardia) clam
Pleuromeris cannada clam | |
Corbula juliana clam | |
Pholadidea patagonica Philippi 1887 clam | |
"Cardium" pisum Philippi 1887 cockle | |
Dosinia laeviuscula, Dosinia burmeisteri, Dosinia meridonalis, "Chione" patagonica, Austrocallista iheringi, Pitar julianum
Dosinia laeviuscula venus clam
Dosinia burmeisteri venus clam
Dosinia meridonalis Ihering 1897 venus clam
"Chione" patagonica Philippi 1887 venus clam
Austrocallista iheringi Cossmann 1898 venus clam
Pitar julianum venus clam | |
Panopea sierrana clam | |
Gastropoda | |
Solariella osborni snail | |
Cirsotrema rugulosa wentletrap | |
Turritella patagonica turret shell | |
""Polynices" secunda" = Polinices, ""Polynices" subtenuis" = Polinices subtenuis
""Polynices" secunda" = Polinices moon snail
""Polynices" subtenuis" = Polinices subtenuis Ihering 1907 moon snail | |
Hipponix costata hoof shell | |
""Proscaphella" gracilior" = Miomelon gracilis
""Proscaphella" gracilior" = Miomelon gracilis Philippi 1887 volute | |
Trophon santacrucensis Ihering 1897 murex snail | |
Struthiolarella ornata snail | |
"Calyptraea" juliana slipper shell
"Calyptraea" pileus Lamarck 1822 slipper shell |