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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 ...
The ordovician system in the Argentine Eastern Cordillera
(Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto Superior de Correlación Geológica, 2003)
The purpose of this chapter is to offer a synthesis on the main geological features of the Ordovician deposits that crop out in the Eastern Cordillera (Cordillera Oriental) of northwestern Argentina. The regional and ...
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, ...
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 ...
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. ...
South America’s earliest (Ordovician, Floian) crinoids
(Paleontological Society, 2015-12)
Two new Early Ordovician crinoids have been discovered in Gondwanan rocks of northwest Argentina. Ramseyocrinus argentinus n. sp., among the most complete for the genus, aids in reconstructing key morphology. Ramseyocrinus ...
Ordovician conodonts from Peru: new data and reappraisal - [Poster]
(Université Claude Bernard Lyon IFR, 2016-12)
Ordovician conodont faunas are poorly known from the northern part of the Central Andean Basin, in contrast with data from the northwest of Argentina and south of Bolivia, areas located in the southern part of the same ...
Cladistics and mass extinctions: the example of conulariids (Scyphozoa, Cnidaria) and the End Ordovician Extinction Event
(Oxford, 2014)
The End Ordovician Extinction Event (EOEE) had little impact on supra-specific diversity and disparity within the order Conulariida (Scyphozoa, Cnidaria). With two possible exceptions (Exoconularia and Glyptoconularia), ...
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 ...
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 ...