Isla Grande de Tierra del Fuego (Early Oligocene): Early/Lower Oligocene, Argentina

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
unclassified
Pachymagus cf. venter
Anthozoa - Scleractinia - Flabellidae
Flabellum cf. cuneiforme (Lonsdale 1845)
Subspecies: F. cf. cuneiforme wailesi
Gastropoda - Neotaenioglossa - Calyptraeidae
Calyptraea sp. Lamarck 1799
Calyptraea cf. merriami
Gastropoda - Turritellidae
Turritella ambulacrum Sowerby 1846
Subspecies: T. ambulacrum sylva
Gastropoda - Aporrhaidae
"Chenopus" santacruzensis
Gastropoda - Struthiolariidae
Struthiolarella densestriata (Ihering 1897)
Gastropoda - Neogastropoda - Buccinidae
"Nassa" fueguina Steinmann and Wilckens 1908
"Verconella" iheringi
Austrocominella fueguensis (Ihering 1907)
Gastropoda - Neogastropoda - Muricidae
Trophon sp. Montfort 1810
Gastropoda - Neogastropoda - Volutidae
Miomelon becki
Subspecies: M. becki cannada
Miomelon cf. gracilior (Ihering 1896)
synonym of Miomelon gracilis
Gastropoda - Naticidae
Polinices (Euspira) santacruzensis
original and current combination Euspira
Polinices (Euspira) sp. (Agassiz 1837)
original and current combination Euspira
Gastropoda - Heterostropha - Acteonidae
"Actaeon" chilensis
replaced by Acteon
Bivalvia - Arcida - Cucullaeidae
Cucullaea (Cucullona) alta Sowerby 1846
Bivalvia - Arcida - Glycymerididae
Glycymeris cf. cuevensis
Bivalvia - Mytilida - Mytilidae
Modiolus ameghinoi (Ihering 1907)
Bivalvia - Lucinida - Lucinidae
Miltha promaucana (Philippi 1877)
recombined as Lucinoma promaucana
Subspecies: M. promaucana crucialis
Bivalvia - Cardiida - Veneridae
Eurhomalea cf. fuenzalidai (Philippi 1887)
Bivalvia - Carditida - Carditidae
Cardiocardita inaequalis (Philippi 1887)
Pleuromeris elegantoides (Ortman 1902)
Bivalvia - Nuculida - Nuculidae
Nucula (Leionucula) grandis n. sp. Malumian et al. 1978
see common names

Geography
Country:Argentina
Coordinates: 50.2° South, 72.9° West (view map)
Paleocoordinates:52.1° South, 63.9° West
Basis of coordinate:based on nearby landmark
Geographic resolution:local area
Time
Period:Paleogene Epoch:Oligocene
Stage:Rupelian 10 m.y. bin:Cenozoic 4
Key time interval:Early/Lower Oligocene
Age range of interval:33.90000 - 28.40000 m.y. ago
Stratigraphy
Stratigraphic resolution:formation
Stratigraphy comments: STRATIGRAPHIC RELATIONS: Lithostratigraphy not stated. AGE: Paleontological evidence suggests an Eocene to Early Oligocene age for this fauna. Strong faunal similarity to San Julian (Eocene-Oligocene), Monte Leon (Oligocene) and Loreto Formations (Oligocene-Miocene). Several taxa also recorded in the Millongue and Boqueron Formations of Chile. An Oligocene age is assigned here on the basis of commonality in age between correlated formations. STRATIGRAPHIC POSITION: Composite collection from unit within local area.
Lithology and environment
Primary lithology:shelly/skeletal poorly lithified conglomeratic sandstone
Includes fossils?Y
Lithology description: SPECIFIC LITHOLOGY: Conglomeratic sandstone containing many skeletal elements. LITHIFICATION: Poorly lithified on the basis of figured specimens (gastropods with sediment filled apertures, sediment adhearing to external surfaces),
Environment:offshore
Geology comments: ENVIRONMENT: No environmental data reported in text. Faunal composition suggests an inner shelf siliciclastic environment, though not very shallow.
Taphonomy
Modes of preservation:body,original aragonite,original calcite
Degree of concentration:concentrated
Size of fossils:macrofossils
Preservation of anatomical detail:good
Articulated whole bodies:some
Collection methods and comments
Collection methods:selective quarrying,field collection
Reason for describing collection:taxonomic analysis
Collection method comments: COLLECTOR: M. Doello-Jurado, N. Malumian and H. H. Camacho, possibly R. Gorrono, plus existing collections in the Museo Argentino de Ciencias Naturales and Servico Geologico Nacional. REPOSITORY: Museo Argentino de Ciencias Naturales and Servico Geologico Nacional.
Taxonomic list comments:COVERAGE: Exhaustive for bivalvia and gastropoda. Corals, brachiopods, foraminifera and palynomorhs apparently also present. NOMENCLATURE: Authoritative publication that appears to use fairly modern nomenclature, and subgeneric and species-level resolution.
Metadata
Database number:66146
Authorizer:A. Hendy Enterer:A. Hendy
Research group:marine invertebrate
Created:2006-10-02 11:28:48 Last modified:2013-11-25 13:37:23
Access level:group members Released:2006-10-02 11:28:47
Creative Commons license:CC BY
Reference information

Primary reference:

18943. N. Malumian, H. H. Camacho, and R. Gorrono. 1978. Molluscos del Terciario Inferior ("Magallanense") de la Isla Grande de Tierra del Fuego (Republica Argentina). Ameghiniana 15(3-4):265-284 [A. Hendy/A. Hendy]