Unexpected diversity of small eukaryotes in deep-sea Antarctic plankton

  title={Unexpected diversity of small eukaryotes in deep-sea Antarctic plankton},
  author={Purificaci{\'o}n L{\'o}pez‐Garc{\'i}a and Francisco Rodr{\'i}guez-Valera and Carlos Pedr{\'o}s-Ali{\'o} and David Moreira},
Phylogenetic information from ribosomal RNA genes directly amplified from the environment changed our view of the biosphere, revealing an extraordinary diversity of previously undetected prokaryotic lineages. Using ribosomal RNA genes from marine picoplankton, several new groups of bacteria and archaea have been identified, some of which are abundant. Little is known, however, about the diversity of the smallest planktonic eukaryotes, and available information in general concerns the… 

Eukaryotic plankton diversity in the sunlit ocean

Diversity emerged at all taxonomic levels, both within the groups comprising the ~11,200 cataloged morphospecies of eukaryotic plankton and among twice as many other deep-branching lineages of unappreciated importance in plankton ecology studies.

Unveiling the Organisms behind Novel Eukaryotic Ribosomal DNA Sequences from the Ocean

One lineage accounted for up to 46% (average during an annual cycle, 19%) of heterotrophic flagellates in a coastal environment, providing evidence that novel stramenopiles are important and unrecognized components of the total stock of bacterial grazers.

Novel Eukaryotic Lineages Inferred from Small-Subunit rRNA Analyses of Oxygen-Depleted Marine Environments

A significant number of detected rRNA sequences exhibited no affiliation to known organisms and sequences and thus represent novel lineages of the highest taxonomical order, most of them branching off the base of the global phylogenetic tree, suggesting that oxygen-depleted environments harbor diverse communities of novel organisms, which may provide an interesting window into the early evolution of eukaryotes.

The extent of protist diversity: insights from molecular ecology of freshwater eukaryotes

A molecular survey of small subunit ribosomal RNA genes in water and sediment samples of two ponds shows that protist diversity is very high, and suggests that, contrary to current ideas, the diversity of freshwater protists is far from being completely described.

Study of Genetic Diversity of Eukaryotic Picoplankton in Different Oceanic Regions by Small-Subunit rRNA Gene Cloning and Sequencing

The diversity of marine picoeukaryotes was determined by sequencing cloned 18S rRNA genes in five genetic libraries from North Atlantic, Southern Ocean, and Mediterranean Sea surface waters, and the phylogenetic diversity in each library was rather great, and each library included many different OTUs and members of very distantly related phylogenetic groups.

Microbial eukaryote diversity in the marine oxygen minimum zone off northern Chile

Variation in OMZ microeukaryote composition is revealed, helping to identify clades with potential adaptations to oxygen-depletion, compared to those from other low-oxygen sites.

The molecular diversity of freshwater picoeukaryotes from an oligotrophic lake reveals diverse, distinctive and globally dispersed lineages.

Many freshwater phylogenetic groups identified in this study appeared unrelated to picoeukaryotic sequences identified in marine ecosystems, suggesting that aspects of eukaryote microbial diversity are specific to certain aquatic environments.

Novel kingdom-level eukaryotic diversity in anoxic environments

  • S. DawsonN. Pace
  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 2002
A cultivation-independent, molecular phylogenetic survey of three anoxic sediments found many previously unrecognized eukaryotes, including representatives of seven lineages that are not specifically related to any known organisms at the kingdom-level and branch below the Eukaryotic “crown” radiation of animals, plants, fungi, stramenopiles, etc.

Picoplankton diversity in the Arctic Ocean and surrounding seas

An overview of microbial diversity revealed by environmental surveys of the small subunit rRNA gene (SS rRNA), which is the most widely used marker for identifying microbes, is provided.



Novel major archaebacterial group from marine plankton

16S rRNA sequences obtained from Pacific Ocean bacterioplankton samples collected from depths of 100 m and 500 m are reported and it is suggested that these sequences are from a previously undescribed archaebacterial group that may have diverged from the ancestors of characterized organisms very early in evolution.

Vertical distribution and phylogenetic characterization of marine planktonic Archaea in the Santa Barbara Channel

Data suggest that marine planktonic crenarchaea and euryarchaea of temperate coastal habitats thrive in different zones of the water column, and that its members constitute a significant fraction of the prokaryotic biomass in subsurface coastal waters.

Genetic diversity in Sargasso Sea bacterioplankton

The phylogenetically analysed clone libraries of eubacterial 16S ribosomal RNA genes amplified from natural populations of Sargasso Sea picoplankton indicate the presence of a novel microbial group, the SAR 11 cluster, which appears to be a significant component of this oligotrophic bacterioplankton community.

Archaea in coastal marine environments.

  • E. Delong
  • Environmental Science, Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 1992
Evidence for the widespread occurrence of unusual archaea in oxygenated coastal surface waters of North America is provided and it is suggested that these microorganisms represent undescribed physiological types of archaea, which reside and compete with aerobic, mesophilic eubacteria in marine coastal environments.

A molecular view of microbial diversity and the biosphere.

Over three decades of molecular-phylogenetic studies, researchers have compiled an increasingly robust map of evolutionary diversification showing that the main diversity of life is microbial,

Extreme differences in rates of molecular evolution of foraminifera revealed by comparison of ribosomal DNA sequences and the fossil record.

It is estimated that the rate of rDNA evolution in planktonic foraminifera is 50 to 100 times faster than in some benthic foraminaifera, and the use of the maximum-likelihood method and limitation of analyzed sites to the most conserved parts of the SSU rRNA molecule render molecular and paleontological data generally congruent.

Long-branch attraction and the rDNA model of early eukaryotic evolution.

The results suggest that the basal eurkaryotic topology drawn from rDNA analyses may be, in reality, an artifact of variation in the rate of molecular evolution among eukaryotic taxa.

Diversity and Abundance of Bolidophyceae (Heterokonta) in Two Oceanic Regions

The contribution of the Bolidophyceae to the eukaryotic DNA in both Pacific and Mediterranean waters is estimated to be lower than 1%, and high-performance liquid chromatography analyses of fucoxanthin indicated that less than 4% of the total chlorophyll a in the picoplanktonic fraction in the equatorial Pacific was due to Bolid morphology.

Molecular evidence for genetic mixing of Arctic and Antarctic subpolar populations of planktonic foraminifers

This work identifies at least one identical genotype in all three morphospecies in both the Arctic and Antarctic subpolar provinces, indicating that trans-tropical gene flow must have occurred, and reveals that foraminiferal morphos pecies can consist of a complex of genetic types.

Biogeochemical evidence for dinoflagellate ancestors in the early cambrian

Examination of dinoflagellate-specific biological markers in concentrated microfossils with known morphology identified ancient din oflageLLate ancestors from the Early Cambrian.