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First Ordovician Foraminifera from South America: A Darriwilian (Middle Ordovician) fauna from the San Juan Formation, Argentina
(Micropaleontology Press, 2009-12)
The first Ordovician foraminifers in South America are described from Middle Ordovician (Darriwilian)strata of the upper part of the San Juan Formation, Argentina. The foraminifers are found together with conodonts of the ...
Ordovician gastropods from Argentina
(The Czech Geological Society, 2001-12)
Ordovician (Arenig to Lower Llanvirn) gastropods are summarized from the San Juan Formation, in the San Juan Precordillera of Argentina. Preservation is poor, but at least fourteen genera representing bellerophontoids, ...
Early Ordovician (Floian) ostracods from the Cordillera Oriental, Northwest Argentina
(John Wiley & Sons Ltd, 2011-11)
The ostracod fauna from the Floian (Lower Ordovician) strata of the Cordillera Oriental, Argentina (Acoite Formation) are documented. One new genus Acoitella and four species are recognized, two of which are new (Nanopsis ...
Acritarchs of peri-Gondwana at the Lower and Middle Ordovician stage boundaries
(Instituto Superior de Correlación Geológica, 2003-08)
Although acritarchs have been studied mostly for stratigraphic purposes (often in sediments devoid of other fossils), their biostratigraphic potential has not yet been fully exploited in the Ordovician. While another group ...
The oldest Ordovician foraminifers (Oepikodus evae conodont Zone, Floian) from South America
(Elsevier France-Editions Scientifiques Medicales Elsevier, 2011-06)
The oldest occurrences of the monothalamous foraminifer species. Amphitremoida longa Nestell and Tolmacheva and A. laevis Nestell and Tolmacheva are found in the San Juan Formation together with conodonts of the Oepikodus ...
Stratigraphical distribution of the Ordovician conodont Erraticodon Dzik in Argentina
(Elsevier, 2013-08)
Three different species of the Ordovician genus Erraticodon Dzik are described and illustrated. E. patu Cooper is reported from the Lower-Midde Ordovician strata of the Acoite and Alto del Cóndor formations. E. cf. E. ...
The palaeobiogeographical spread of the acritarch Veryhachium in the Early and Middle Ordovician and its impact on biostratigraphical applications
(Taylor & Francis Ltd, 2014-03)
The genus Veryhachium Deunff, 1954, is one of the most frequently documented acritarch genera, being recorded from the Early Ordovician to the Neogene. Detailed investigations show that Veryhachium species first appeared ...
Ordovician (Floian-lower Darriwilian) conodont biofacies of the San Juan Formation in the Cerro Viejo of Huaco, Argentine Precordillera
(Elsevier Science, 2019-12)
The conodont biofacies from the San Juan Formation at the Cerro Viejo of Huaco, Central Precordillera of Argentina, are analyzed for the identification of faunal dynamics and sea-level changes. The Prioniodus elegans and ...
Trilobites from the Suri Formation (Lower Ordovician; Floian), Famatina Belt, Argentina
(Association of Australasian Palaeontologists, 2009-11)
A new trilobite fauna from the lower part of the Suri Formation (upper Floian) exposed in the central Famatina Belt, west Argentina, is reported. Three new species are described: Dividuagnostus tortelloi sp. nov., Bienvillia ...