New acritarchs from the late Cenozoic of the southern North Sea Basin and the North Atlantic realm

Abstract

Biostratigraphical investigations of Miocene deposits from the southern North Sea Basin, the Oligocene and Miocene of the Bahamas, and the lower Pliocene of northern Iceland revealed the presence of new acritarch species. Halodinium eirikssonii n. sp. is recovered from the lower Pliocene Serripes Zone of the Tjörnes beds in northern Iceland, where its range is well constrained through magnetostratigraphy and biostratigraphy with dinoflagellate cysts. Leiosphaeridia spongiosa n. sp. is recovered from lower to upper Miocene deposits of the southern North Sea Basin and from upper Oligocene and Miocene deposits of the Bahamas. Palaeostomocystis orbiculata n. sp. appears restricted to the middle Miocene of the North Sea Basin

Late Neogene dinoflagellate cyst and acritarch biostratigraphy for Ocean Drilling Program Hole 642B, Norwegian Sea

“…Furthermore, our knowledge of late Neogene dinoflagellate cysts and acritarchs has increased steadily since the 1990s following major taxonomic advances and the formal description of numerous new dinoflagellate cyst and acritarch taxa (e.g. Head, 1993Head, , 1996Head, , 1997Head and Norris, 2003;De Schepper et al, 2004;Head, 2008a, 2014;Schreck et al, 2012;Verhoeven et al, 2014;Versteegh and Zevenboom, 1995). Dinoflagellate cysts have been successfully applied for establishing a detailed late Neogene stratigraphy in the eastern North Atlantic Head, 2008a, 2009), Iceland Sea (Verhoeven et al, 2011;Schreck et al, 2012) and the North Sea Basin (Louwye et al, 2004;Dybkjaer and Piasecki, 2010), suggesting that this should also be achievable in the Norwegian Sea.…”

Dinocyst and acritarch biostratigraphy of the Late Pliocene to Early Pleistocene at Integrated Ocean Drilling Program Site U1307 in the Labrador Sea

“…The pioneering work of de Vernal and Mudie (1989) identified a rich palynological assemblage, including several new taxa characteristics of the Pliocene that were left in open nomenclature. The knowledge of the North Atlantic Neogene dinocyst and acritarchs has improved considerably over the last two decades as several new taxa were described (Head, 1993(Head, , 1996(Head, , 1997Versteegh and Zevenboom, 1995;Head and Norris, 2003;De Schepper et al, 2004;De Schepper andHead, 2008a, 2014;Schreck et al, 2012;Verhoeven et al, 2014). Using the state-of-the-art taxonomy, we identified 115 dinocyst and 24 acritarch taxa at Site U1307, which represents a much higher species diversity than the one reported by de Vernal and Mudie (1989) which reported ∼ 51 dinocyst and ∼ 8 acritarch taxa at ODP Hole 646B.…”

“…Hence, in the Neogene sediments of the subpolar North Atlantic and North Pacific oceans, organic-walled microfossils such as dinoflagellate cysts (hereafter dinocysts) and acritarchs are very useful to establish biostratigraphical schemes De Schepper andHead, 2008a, b, 2009;De Schepper et al, 2009Dybkjaer and Piasecki, 2010;Verhoeven et al, 2011;Schreck et al, 2012;Zorzi et al, 2019). Since the 1980s, several regional studies across the North Atlantic and the Nordic Seas (the Iceland Sea and the Norwegian Sea) have led to the improvement of the taxonomy of dinocysts and acritarchs (Head, 1993(Head, , 1996(Head, , 1997Versteegh and Zevenboom, 1995;Head and Norris, 2003;De Schepper et al, 2004;De Schepper andHead, 2008a, 2014;Schreck et al, 2012;Verhoeven et al, 2014) and to the development of calibrated biozonations that may allow correlations (De Schepper and Head, 2009;Schreck et al, 2012;De Schepper et al, 2017). Moreover, the paleoecological affinities of extinct Neogene taxa were also explored to better understand the significance of bioevents Hennissen et al, 2015Hennissen et al, , 2017Schreck et al, 2017).…”

Baffin Bay late Neogene palynostratigraphy at Ocean Drilling Program Site 645

“…Since then, major progress has been made concerning Neogene dinocyst and acritarch taxonomy (Head 1993(Head , 1996(Head , 1997Versteegh and Zevenboom 1995;Head and Norris 2003;De Schepper et al 2004;DeSchepper andHead 2008a, 2014;Schreck et al 2012;Verhoeven et al 2014) and the biostratigraphic scheme for the North Atlantic and Arctic oceans has been completely revised (De Schepper and Head 2009;De Schepper et al 2015Schreck et al 2012;Mattingsdal et al 2014;Matthiessen et al 2018). The abovementioned studies yield relatively well documented regional palynostratigraphy and provide us with the opportunity to improve the biostratigraphic scheme of ODP Site 645 and to document paleo-environmental conditions in the light of a better constrained stratigraphical context.…”