Ergebnisse der Foraminiferenanalyse zur Quartärstratigraphie in Skandinavien

In Skandinavien sind zahlreiche quartärstratigraphische Untersuchungen mit Hilfe fossiler Foraminiferen durchgeführt worden. Im folgenden wird eine Übersicht über die foraminiferenstratigraphischen Untersuchungen und deren Resultate in Dänemark, Norwegen und Schweden gegeben.researc

A new multi-proxy investigation of Late Quaternary palaeoenvironments along the north-western Barents Sea (Storfjorden Trough Mouth Fan)

A new integrated micropalaeontological study on planktonic and benthic foraminifera, calcareous nannofossils and diatoms was performed on three sediment cores from the Storfjorden Trough Mouth Fan to reconstruct the Late Quaternary palaeoenvironmental and climatic history. Two main intervals were discussed: the last deglaciation (16.2\u201311.7 ka BP) and the Holocene. The age model relies on palaeomagnetic parameters together with 10 radiocarbon dates. Deglacial sediments had largely diluted the biogenic content which was scarce and poorly preserved. The first occurrence of Cibicidoides wuellerstorfi (benthic foraminifer), together with Turborotalita quinqueloba (planktonic foraminifer) and Coscinodiscus spp. (diatoms) at 11.3 ka BP followed the end of the Younger Dryas cold event and marked the beginning of the early Holocene warm period. Diatoms and planktonic foraminifers indicated a warming of the surface water from 10.5 to 9.2 ka BP, identifying the Holocene Thermal Maximum event. Bottom water fauna registered these warming conditions less clearly. Cooling events were identified during the Holocene, in particular the 8.2 ka BP event and the Neoglacial between 3.2 and 2 ka BP, as shown by the presence of cold-water taxa such as Gephyrocapsa muellerae (nannoplankton) and Neogloboquadrina pachyderma (planktonic foraminifer). These events were influenced by sea ice extent, cold or relatively warm current influxes

The genetic diversity, phylogeography and morphology of Elphidiidae (Foraminifera) in the Northeast Atlantic

Genetic characterisation (SSU rRNA genotyping) and Scanning ElectronMicroscope (SEM) imaging of individualtests were used in tandem to determine the modern species richness of the foraminiferal family Elphidiidae(Elphidium, Haynesina and related genera) across the Northeast Atlantic shelf biomes. Specimens were collectedat 25 locations fromthe High Arctic to Iberia, and a total of 1013 individual specimenswere successfully SEMimagedand genotyped. Phylogenetic analyses were carried out in combination with 28 other elphidiid sequencesfrom GenBank and seventeen distinct elphidiid genetic types were identified within the sample set, sevenbeing sequenced for the first time. Genetic types cluster into sevenmain cladeswhich largely represent their generalmorphologicalcharacter. Differences between genetic types at the genetic, morphological and biogeographiclevels are indicative of species level distinction. Their biogeographic distributions, in combination with elphidiidSSU sequences from GenBank and high resolution images from the literature show that each of them exhibitsspecies-specific rather than clade-specific biogeographies. Due to taxonomic uncertainty and divergent taxonomicconcepts between schools, we believe that morphospecies names should not be placed onto molecularphylogenies unless both the morphology and genetic type have been linked to the formally named holotype,or equivalent. Based on strictmorphological criteria,we advocate using only a three-stage approach to taxonomyfor practical application in micropalaeontological studies. It comprises genotyping, the production of a formalmorphological description of the SEM images associated with the genetic type and then the allocation of themost appropriate taxonomic name by comparison with the formal type description. Using this approach, wewere able to apply taxonomic names to fifteen genetic types. One of the remaining two may be potentially cryptic,and one is undescribed in the literature. In general, the phylogeographic distribution is in agreement with ourknowledge of the ecology and biogeographical distribution of the corresponding morphospecies, highlighting thegenerally robust taxonomic framework of the Elphidiidae in time and space

A New Integrated Approach to Taxonomy: The Fusion of Molecular and Morphological Systematics with Type Material in Benthic Foraminifera

This work was supported by NERC grant NE4/G018502/1 and NE/G020310/1 (Website: http://www.nerc.ac.uk). The authors also thank the following for their support the Carnegie Trust for the Universities of Scotland (Website: http://www.carnegie-trust.org) and the Estuarine Coastal and Shelf Science Association (Website: http://www.ecsanews.org). M.S. was also supported by the Swiss National Science Foundation (SNSF), fellowships for advanced researchers PA00P2_126226 and PA00P2_142065 (Website: http://www.snf.ch/en/Pages/default.aspx).A robust and consistent taxonomy underpins the use of fossil material in palaeoenvironmental research and long-term assessment of biodiversity. This study presents a new integrated taxonomic protocol for benthic foraminifera by unequivocally reconciling the traditional taxonomic name to a specific genetic type. To implement this protocol, a fragment of the small subunit ribosomal RNA (SSU rRNA) gene is used in combination with 16 quantitative morphometric variables to fully characterise the benthic foraminiferal species concept of Elphidium williamsoni Haynes, 1973. A combination of live contemporary topotypic specimens, original type specimens and specimens of genetic outliers were utilised in this study. Through a series of multivariate statistical tests we illustrate that genetically characterised topotype specimens are morphologically congruent with both the holotype and paratype specimens of E. williamsoni Haynes, 1973. We present the first clear link between morphologically characterised type material and the unique SSU rRNA genetic type of E. williamsoni. This example provides a standard framework for the benthic foraminifera which bridges the current discontinuity between molecular and morphological lines of evidence, allowing integration with the traditional Linnaean roots of nomenclature to offer a new prospect for taxonomic stability.Publisher PDFPeer reviewe