Stephanopogon

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Stephanopogon
Stephanopogon spec.

Stephanopogon spec.

Systematics
Classification : Creature
Domain : Eukaryotes (eukaryota)
without rank: Excavata
incertae sedis
Genre : Stephanopogon
Scientific name
Stephanopogon
Entz , 1884

Stephanopogon is a protist genusconsisting of six marine specieswhose systematic position within the eukaryotes was not clear for a long time.

features

Stephanopogon species are 20 to 50 micrometers in size, alveoli and infraciliature are missing. There is only one nucleus , but this can be 2 to 16-fold as a homokaryote . The cell mouth sits at the front end, the cristae are disc-shaped. The microtubules of the cell membrane are aligned lengthways.

The numerous, non-flickering flagella , arranged in rows , each have only single kinetosomes . They are sunk into the surface of the cell in the shape of a trumpet and are supported by radially arranged microtubules.

Way of life

All species live near the ground ( benthic ) in the sea to a depth of 100 meters. There they feed on diatoms , flagellates and bacteria . Nothing is known about their sexual reproduction, reproduction by cell division only takes place in the cyst stage .

Systematics

Originally, the genus was counted due to some morphological similarities to the ciliates (Ciliata), due to the lack of a second cell nucleus as the apparently most primitive representatives in a subgroup Primociliata. However Electron microscopy showed the absence yet another important characteristics of ciliates on ( alveoli and infraciliature), so they outsourced since the early 1980s from them and, among other things as a separate phylum Pseudociliata were performed ( "sham ciliates"). Adl et al. on the other hand, in 2005, the genus was classified as unclear ranges incertae sedis among the eukaryotes.

In 2008, independent molecular genetic investigations showed that stephanopogon is the sister taxon of the genus Percolomonas . The clade formed from the two genera in turn is the sister taxon of the Heterolobosea . According to Cavalier-Smith, they represent in their entirety the Percolozoa as the sister of the Euglenozoa .

Newer systematics understand them as part of the Heterolobosea and place them there within the group Tetramitia .

The genus includes six described species:

proof

  • Klaus Hausmann, Norbert Hülsmann, Renate Radek: Protistology , 3rd edition, 2003, p. 63, ISBN 3510652088
  • Sina M. Adl, Alastair GB Simpson, Mark A. Farmer, Robert A. Andersen, O. Roger Anderson, John A. Barta, Samual S. Bowser, Guy Brugerolle, Robert A. Fensome, Suzanne Fredericq, Timothy Y. James, Sergei Karpov, Paul Kugrens, John Krug, Christopher E. Lane, Louise A. Lewis, Jean Lodge, Denis H. Lynn, David G. Mann, Richard M. McCourt, Leonel Mendoza, Øjvind Moestrup, Sharon E. Mozley-Standridge, Thomas A. Nerad, Carol A. Shearer, Alexey V. Smirnov, Frederick W. Spiegel, Max FJR Taylor: The New Higher Level Classification of Eukaryotes with Emphasis on the Taxonomy of Protists. The Journal of Eukaryotic Microbiology 52 (5), 2005; P. 444

proof

  1. ↑ a b Naoji Yubuki, Brian S. Leander: Ultrastructure and molecular phylogeny of Stephanopogon minuta: An enigmatic microeukaryote from marine interstitial environments , In: European Journal of Protistology 44, 2008, pp. 241-253
  2. ↑ Thomas Cavalier-Smith, Sergey Nikolaev: The Zooflagellates Stephanopogon and Percolomonas are a Clade (Class Percolatea: Phylum Percolozoa) In: Journal of Eukaryotic Microbiology, 55 (6), pp. 501-509, 2008
  3. ↑ Adl, SM, Simpson, AGB, Lane, CE, Lukeš, J., Bass, D., Bowser, SS, Brown, MW, Burki, F., Dunthorn, M., Hampl, V., Heiss, A. , Hoppenrath, M., Lara, E., le Gall, L., Lynn, DH, McManus, H., Mitchell, EAD, Mozley-Stanridge, SE, Parfrey, LW, Pawlowski, J., Rueckert, S., Shadwick, L., Schoch, CL, Smirnov, A. and Spiegel, FW: The Revised Classification of Eukaryotes. Journal of Eukaryotic Microbiology , 59: 429-514, 2012, PDF Online

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