acritarch


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acritarch

[′ak·rə‚tark]
(paleontology)
A unicellular microfossil of unknown or uncertain biological origin that occurs abundantly in strata from the Precambrian and Paleozoic.
References in periodicals archive ?
This acritarch assemblage was termed 'the Kybartai assemblage' by Jankauskas (2002) and corresponds to assemblage 3 by Hagenfeldt & Bjerkeus (1991).
In these measurements acritarch CAI values were used.
He and other paleontologists have suspected for some time that a fraction of the known acritarch species represent predecessors of modern dinoflagellates.
In addition to the index taxon, Asteridium tornatum (Volkova), the Lontova acritarch assemblage of the East European Craton is characterized by the occurrence of Granomarginata squamacea Volkova, G.
The outcrops also contain undescribed pre-Agnostus pisiformis acritarch assemblages that confirm the timing of their deposition to the Cambrian Epoch 3 (Palacios et al.
Early Tremadoc acritarch microfossils were reported by Doyle (1979) and confirmed by Palacios et al.
The age of the Kotlin sandstone is rather loosely constrained (< 570 Ma), whereas the Lontova Formation is represented by the sub-trilobitic acritarch assemblage of Asteridium tornatum-C.
Nevertheless, at least four distinctive acritarch assemblages can be recognized, providing particular taxonomic characteristics of the studied strata.
and the acritarch assemblage found from two levels in the Maekalda section near the centre of Tallinn (15 km west of the Ulgase section) allow tentative correlation of the Ulgase Formation in Tallinn and its environs with the Olenus trilobite Biozone (Mens et al.