Telonemia is a

phylum In biology, a phylum (; plural: phyla) is a level of classification or taxonomic rank below kingdom and above class. Traditionally, in botany the term division has been used instead of phylum, although the International Code of Nomenclature ...

of microscopic

eukaryote Eukaryotes () are organisms whose cells have a nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the three domains of life. Bacter ...

single-celled organism A unicellular organism, also known as a single-celled organism, is an organism that consists of a single cell, unlike a multicellular organism that consists of multiple cells. Organisms fall into two general categories: prokaryotic organisms an ...

s. They were formerly classified as

protist A protist () is any eukaryotic organism (that is, an organism whose cells contain a cell nucleus) that is not an animal, plant, or fungus. While it is likely that protists share a common ancestor (the last eukaryotic common ancestor), the e ...

s until that kingdom fell out of general use, and are suggested to have

evolutionary Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variati ...

significance in being a possible transitional form between ecologically important heterotrophic and

photosynthetic Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities. Some of this chemical energy is stored in ...

species among chromalveolates. One paper places them in the

SAR supergroup The SAR supergroup, also just SAR or Harosa, is a clade that includes stramenopiles ( heterokonts), alveolates, and Rhizaria. The name is an acronym derived from the first letters of each of these clades; it has been alternatively spelled "RAS". ...

. Phylogenomic analyses of 127 genes place Telonemia with Centroheliozoa in a group also consisting of cryptomonads and

haptophyte The haptophytes, classified either as the Haptophyta, Haptophytina or Prymnesiophyta (named for '' Prymnesium''), are a clade of algae. The names Haptophyceae or Prymnesiophyceae are sometimes used instead. This ending implies classification at ...

s (see Cryptomonads-haptophytes assemblage). Although they have been studied in primarily marine environments, they have also been found in freshwater. Shalchian-Tabrizi ''et al'' say that 18S rDNA sequences in the phylum formed two major groups, Group 1 and 2, including ''T. subtilis'' and ''T. antarcticum'' respectively, and that these were further sub-divided into several statistically supported clades of sequences with restricted geographic distribution. Species of Telonemia are heterotrophic predators, feeding on a wide range of bacteria and pico- to nano-sized phytoplankton.

Chloroplast A chloroplast () is a type of membrane-bound organelle known as a plastid that conducts photosynthesis mostly in plant and algal cells. The photosynthetic pigment chlorophyll captures the energy from sunlight, converts it, and stores it i ...

s have not been observed in any of the investigated species. By using specific PCR primers, they revealed a much larger diversity of Telonemia from environmental samples than previously uncovered by eukaryote-wide primers. They are globally distributed in marine waters and are frequently encountered in environmental clone libraries. The evolutionary origin of Telonemia was inferred from phylogenetic reconstruction of single- and concatenated sequences obtained from both cultured strains and environmental clones. Pawlowski identifies it as a micro-kingdom. It is considered sister of the SAR group.

Species

Although only two species have been described formally, DNA sequences collected from seawater suggest there are many more species which have not yet been described. * Class

Telonemea Telonemia is a phylum of microscopic eukaryote, single-celled organisms. They were formerly classified as protists until that kingdom fell out of general use, and are suggested to have evolutionary significance in being a possible transitional fo ...

Cavalier-Smith 1993 elonemia Shalchian-Tabrizi 2006** Order

Telonemida Telonemia is a phylum of microscopic eukaryote, single-celled organisms. They were formerly classified as protists until that kingdom fell out of general use, and are suggested to have evolutionary significance in being a possible transitional fo ...

Cavalier-Smith 1993 *** Family

Telonemidae Telonemia is a phylum of microscopic eukaryote, single-celled organisms. They were formerly classified as protists until that kingdom fell out of general use, and are suggested to have evolutionary significance in being a possible transitional fo ...

Cavalier-Smith 1993 **** Genera '' Lateronema'' Cavalier-Smith 2015 ***** Species ''Lateronema antarctica'' (Thomsen 2005) Cavalier-Smith 2015 'Telonema antarctica'' Thomsen 1992**** Genera ''

Telonema ''Telonema'' is a genus of single-celled organisms. Some sources group ''Telonema'' within the cryptomonads-haptophytes assemblage. It is sometimes assigned to a unique phylum, Telonemia Telonemia is a phylum of microscopic eukaryote, single-c ...

'' Griessmann 1913 ***** Species ''Telonema subtile'' Griessmann 1913 'Telonema subtilis'' Griessmann, 1913

History

The genus ''

'' was described in 1913 by Griessmann.

References

External links

Taxonomy
from the Taxonomy Browser of the

National Center for Biotechnology Information The National Center for Biotechnology Information (NCBI) is part of the United States National Library of Medicine (NLM), a branch of the National Institutes of Health (NIH). It is approved and funded by the government of the United States. Th ...

.
Images, etc.
from iSpecies.org {{Taxonbar, from=Q1782621 Hacrobia Enigmatic eukaryote taxa Bikont phyla