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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 ...
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 ...
A lowermost Ordovician tabulate-like coralomorph from the Precordillera of western Argentina: a main component of a reef-framework consortium
(Paleontological Society, 2016-12)
Although putative corals of uncertain affinities occur in the early Cambrian, the earliest definite tabulatecorals have not been described prior to the Early Ordovician in North America. This paper reports a new findingof ...
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 ...
Ordovician sponge spicules from Spitsbergen, Nevada and Newfoundland: new evidence for hexactinellid and demosponge early diversification
(Taylor & Francis, 2014-02)
Unusually well-preserved spicule assemblages from three Lower to Middle Ordovician localities are examined: Spitsbergen (Floian-Dapingian), Nevada (Vinini Formation, Dapingian) and Newfoundland (Cow Head Group, Tremadocian-lower ...
Lower Ordovician (late Tremadocian?- Floian) palynomorphs from the Llanos Basin, Colombia: Biostratigraphic and paleogeographic significance
(Elsevier Science, 2019-06)
Four core and fifteen cutting samples of well RH-2 from the Ordovician of the Llanos Basin, Colombia, were palynologically analyzed. They yielded mostly diverse and well-preserved marine palynomorph assemblages, dominated ...
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 ...
Early Ordovician trilobites from the Nazareno Area, northwestern Argentina
(Paleontological Society, 2014-09)
The upper part of the Santa Rosita Formation (Ordovician, Tremadocian) in the Nazareno area, Cordillera Oriental, northwestern Argentina, records the vertical passage of high-energy, shallow water platform environments to ...