Paramecium - Deutsche Gesellschaft für Protozoologie / German ...

Heterotrophic nanoflagellates show biogeographies!
Hartmut Arndt, Frank Nitsche, Frank Scheckenbach, Claudia
Wylezich
Allgemeine Ökologie, Zoologisches Institut der Universität zu Köln
Protist diversity is still controversially discussed. One group of protistologists
assumes a relatively low number of protistan species compared
to their low size due to assumed high rates of dispersal and low
speciation rates. Another group of protistologists assumes a high protistan
diversity similar to other groups of eukaryotes claiming a high
number of cryptic species behind each nominal species. We summarise
investigations of heterotrophic nanoflagellates regarding their
diversity and distribution patterns. We included samples from the largest,
though seldom investigated parts of the biosphere, deep sea,
groundwater and polar regions. We will show examples clearly indicating
biogeographies in nanoflagellates (in addition to those already
known for ciliates). According to our recent estimates, protists as the
most abundant eukaryotic key players in most ecosystems worldwide,
the evolutionary oldest and phylogenetically most diverse eukaryotes
should account for a considerable (if not the largest) proportion
of Earth’s eukaryotic diversity. The knowledge of the number of protist
species is not trivial but fundamental for the understanding the
Earth’s biodiversity and ecosystem functioning.
hartmut.arndt@uni-koeln.de
nitsche_frank@hotmail.com
fschecke@uni-koeln.de
claudia.wylezich@uni-koeln.de
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