Thaumatomastix

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Thaumatomastix
Algen I. (Schizophyceen, Flagellaten, Peridineen) (1910) (17762314958).jpg
Thaumatomastix sp. (fig. 18-19)
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Clade: Diaphoretickes
Clade: SAR
Phylum: Cercozoa
Class: Imbricatea
Order: Thaumatomonadida
Family: Thaumatomastigidae
Genus: Thaumatomastix
Lauterborn, 1899
Type species
Thaumatomastix setifera
(Lauterborn 1896) Lemmermann 1908
Synonyms
  • ChrysosphaerellaBalonov 1980 non Lauterborn 1896
  • SpiniferomonasNicholls 1984 non Takahashi 1973
  • ThaumatonemaLauterborn 1896 non Greville 1863

Thaumatomastix is a protist genus of the order Thaumatomonadida , within the phylum Cercozoa and the class Imbricatea. Its species are aquatic, feeding on algae and appearing in waters of a wide range of temperatures and salinities, and are 15-50 micrometers long. They can interchange between flagellated and amoeboid forms, and are notable for being covered in both spiny and flattened siliceous scales. [1]

Contents

Etymology

The genus was named by Robert Lauterborn in 1899. [2] Thauma in Greek can mean ‘miracle,’ ‘wonder,’ or ‘marvel,’ while mastix is a suffix (also Greek-derived) that can be used to mean ‘scourge’ or ‘whip,’ which may refer to the organism’s flagella.

History of knowledge

The genus was first identified in 1899 by Robert Lauterborn, a German protozoologist. [2] Since then several new species have been discovered within the genus. However, analyses of ribosomal DNA have indicated that Thaumatomastix may in fact be a paraphyletic group, [1] and have resulted in seven species (T. formosa, T. fragilis, T. fusiformis, T. groenlandika, T. igloolica, T. spinosa, and T. splendida) being reclassified under the genus Reckertia in 2011. [3] It has also been recently suggested that the genus be split into three separate genera, with the others being Ovaloplaca and Thaumatospina. [4]

Habitat and ecology

Thaumatomastix is found in marine and freshwater environments, over a wide range of salinities and temperatures. Though organisms may be found amidst plankton, they most often occur in sediments. Comparison of their ribosomal DNA sequences with cloned partial sequences has indicated that they can survive in suboxic or even anoxic environments. [1] Thaumatomastix are phagotrophs, with some known to feed on algae. [2] Many species have been primarily observed via whole mounts rather than living samples, and much about their behavior in their natural environment remains unknown. In culture, they have been noted to thrive in samples where suspended sediment particles are allowed to settle. [5]

Description

A typical organism of the genus Thaumatomastix is single-celled and heterotrophic, with a 15-50 micrometer body covered in siliceous scales and spines. [1] The body scales can be triangular or elliptical plates, while the spines vary in length between species and are even bifurcated in the case of T. bipartita. The elliptical plates consist of two fused disks with a varying number of perforations, while the spines have three ridges and a collar-like structure near the proximal plate. [4]

Scales are produced by silica deposition vesicles, which remain invaginated in or close to the cell’s mitochondria during their development. Once a scale is fully formed, its vesicle will move to the cell membrane to deposit it there. [5]

Thaumatomastix are biflagellate, with one flagellum being longer than the cell itself, and move around by swimming or gliding. The two flagella emerge from a short furrow at the anterior end of the cell; the shorter one is armored by scales while the longer one is not. [5] Though present in most species, flagella have not been observed in T. tauryanini as of 2012. [2]

In addition to a large anterior nucleus, Thaumatomastix possess one or more vacuoles. Cylindrical structures similar to ejectosomes, contained within vesicles just below the plasma membrane, have also been observed in some species. [1]

Thaumatomastix can produce pseudopodia from the ventral surface of their body in order to feed and will sometimes change from flagellated cells to amoeboid cells and back. As amoeboids, they possess branching pseudopodia which they can use to move across a substrate. [1]

Many of these characteristics are shared by the closely related genus Thaumatomonas. However, Thaumatomastix differs in that it has flagellar scales and a longer anterior flagellum. [1]

Genetic analysis suggests that Thaumatomastix is paraphyletic and may need to be divided into multiple genera. Those with oval-shaped plate scales (Ovoplaca) are closely related to another newly discovered genus, Scutellomonas, which also has oval-shaped scales but does not have spines. This does not hold true for Thaumatomastix with triangular scales, and as a result there is currently some uncertainty as to which species still belong in the genus. Based on the new proposed phylogeny, Thaumatomastix itself would be reduced to contain only the three freshwater species with triangular scales, which are distinguished by a thicker cell boundary layer than their marine relatives. [4]

List of species

Nine species are currently recognized in the genus Thaumatomastix as of 2012. [6]

Related Research Articles

<span class="mw-page-title-main">Flagellate</span> Group of protists with at least one whip-like appendage

A flagellate is a cell or organism with one or more whip-like appendages called flagella. The word flagellate also describes a particular construction characteristic of many prokaryotes and eukaryotes and their means of motion. The term presently does not imply any specific relationship or classification of the organisms that possess flagella. However, the term "flagellate" is included in other terms which are more formally characterized.

<span class="mw-page-title-main">Heliomonadida</span> Order of single-celled organisms

The Heliomonadida are a small group of heliozoan amoeboids that are unusual in possessing flagella throughout their life cycle.

<span class="mw-page-title-main">Phaeodarea</span> Class of protists

Phaeodarea or Phaeodaria is a group of amoeboid cercozoan organisms. They are traditionally considered radiolarians, but in molecular trees do not appear to be close relatives of the other groups, and are instead placed among the Cercozoa. They are distinguished by the structure of their central capsule and by the presence of a phaeodium, an aggregate of waste particles within the cell.

<span class="mw-page-title-main">Euglyphida</span> Order of single-celled organisms

The euglyphids are a prominent group of filose amoebae that produce shells or tests that in most described species is reinforced by siliceous scales, plates, and sometimes spines, but this reinforcement is absent in other species. These elements are created within the cell and then assembled on its surface in a more or less regular arrangement, giving the test a textured appearance. There is a single opening for the long slender pseudopods, which capture food and pull the cell across the substrate.

<span class="mw-page-title-main">Monadofilosa</span> Group of protists

Monadofilosa is a grouping of Cercozoa. These organisms are single-celled amoeboid protists.

<span class="mw-page-title-main">Thaumatomonadida</span> Order of single-celled organisms

Thaumatomonadida is an order of flagellates.

Cryomonadida is a group of heterotrophic Rhizaria, that belong to the Cercozoa.

<span class="mw-page-title-main">Thecofilosea</span> Class of single-celled organisms

Thecofilosea is a class of unicellular testate amoebae belonging to the phylum Cercozoa. They are amoeboflagellates, organisms with flagella and pseudopodia, distinguished from other cercozoa by their scale-lacking test composed of organic material. They are closely related to the Imbricatea, a group of testate amoebae with tests composed of inorganic silica scales.

<span class="mw-page-title-main">Sarcomonadea</span> Class of flagellate protists

The sarcomonads or class Sarcomonadea are a group of amoeboid biciliate protists in the phylum Cercozoa. They are characterized by a propensity to move through gliding on their posterior cilium or through filopodia, a lack of scales or external theca, a soft cell surface without obvious cortical filamentous or membranous skeleton, two cilia without scales or hairs, tubular mitochondrial cristae, near-spherical extrusomes, and a microbody attached to the nucleus.

<i>Hemiselmis</i> Genus of single-celled organisms

Hemiselmis is a genus of cryptomonads.

Gyromitus, is a biflagellated thaumatomonas cercozoan found in fresh water. Gyromitus was first discovered in 1939, but, there is still, to this day, very little research done on this organism. The body of the organism is covered in small siliceous oval scales. The two flagella extend from an anterior depression and are used for swimming, not gliding. On occasion this organism can form pseudopods where there are breaks in the silliceous armor, on the ventral side. There are two common species: Gyromitus cordiformis and Gyromitus disomatus.

<i>Katabia</i> Genus of heterotrophic protists

Katabia is a genus of soil-dwelling heterotrophic flagellate cercozoans containing the single species Katabia gromovi, and the only member of family Katabiidae.

<i>Parvilucifera</i> Genus of single-celled organisms

Parvilucifera is a genus of marine alveolates that behave as endoparasites of dinoflagellates. It was described in 1999 by biologists Fredrik Norén and Øjvind Moestrup, who identified the genus among collections of Dinophysis dinoflagellates off the coast of Sweden. Initially mistaken for products of sexual reproduction, the round bodies found within these collections were eventually recognized as sporangia, spherical structures that generate zoospores of a parasitic protist. This organism was later identified as P. infectans, the type species. The examination of this organism and its close genetic relationship to Perkinsus led to the creation of the Perkinsozoa phylum within the Alveolata group.

Mesofila is a genus of freshwater heterotrophic protists of the phylum Cercozoa. It is the only genus in the family Mesofilidae. It is a monotypic genus, with the sole species M. limnetica.

Minimassisteria is a marine bacterivorous genus of protists with only one species, M. diva, that presents three different lifestyle forms. It has a widespread geographic distribution. It is an amoeboflagellate most closely related to Massisteria, and together comprise the family Massisteriidae.

<span class="mw-page-title-main">Glissomonadida</span> Order of protists

The glissomonads are a group of bacterivorous gliding flagellated protists that compose the order Glissomonadida, in the amoeboflagellate phylum Cercozoa. They comprise a vast, largely undescribed diversity of soil and freshwater organisms. They are the sister group to cercomonads; the two orders form a solid clade of gliding soil-dwelling flagellates called Pediglissa.

<span class="mw-page-title-main">Euglyphia (protist)</span> Superorder of protists

Euglyphia is a group of imbricate protists in the phylum Cercozoa. They are unicellular eukaryotes characterized by a cell body covered in large imbricate scales, and an apical aperture through which they extend either filose pseudopodia or two cilia of different sizes that are not used for gliding.

Pediglissa is a subclass of phagotrophic protists that inhabit soil or freshwater habitats. They were defined in 2018 according to phylogenetic analyses that showed a clade containing the orders Cercomonadida and Glissomonadida. They're the sister group of Paracercomonadida.

<span class="mw-page-title-main">Viridiraptoridae</span> Family of predatorial protists

Viridiraptoridae, previously known as clade X, is a clade of heterotrophic protists in the phylum Cercozoa. They're a family of glissomonads, a group containing a vast, mostly undescribed diversity of soil and freshwater organisms.

Limnofila is a genus of heterotrophic protists that live in freshwater habitats and feed on bacteria. They are also present in the soil ecosystem, where they play an important role as predators of bacteria. They are classified as a single family Limnofilidae and order Limnofilida.

References

  1. 1 2 3 4 5 6 7 Ota, Shuhei; Eikrem, Wenche; Edvardsen, Bente (2012-07-01). "Ultrastructure and Molecular Phylogeny of Thaumatomonads (Cercozoa) with Emphasis on Thaumatomastix salina from Oslofjorden, Norway". Protist. 163 (4): 560–573. doi:10.1016/j.protis.2011.10.007. ISSN   1434-4610. PMID   22177453.
  2. 1 2 3 4 "Thaumatomastix Lauterborn, 1899 :: Algaebase". www.algaebase.org. Retrieved 2020-04-30.
  3. Howe, Alexis T.; Bass, David; Scoble, Josephine M.; Lewis, Rhodri; Vickerman, Keith; Arndt, Hartmut; Cavalier-Smith, Thomas (2011). "Novel Cultured Protists Identify Deep-branching Environmental DNA Clades of Cercozoa: New Genera Tremula, Micrometopion, Minimassisteria, Nudifila, Peregrinia". Protist. 162 (2): 332–372. doi:10.1016/j.protis.2010.10.002. ISSN   1434-4610. PMID   21295519.
  4. 1 2 3 Scoble, Josephine M.; Cavalier-Smith, Thomas (2014-06-01). "Scale evolution, sequence phylogeny, and taxonomy of thaumatomonad Cercozoa: 11 new species and new genera Scutellomonas, Cowlomonas, Thaumatospina and Ovaloplaca". European Journal of Protistology. 50 (3): 270–313. doi:10.1016/j.ejop.2013.12.005. ISSN   0932-4739. PMID   24667165.
  5. 1 2 3 THOMSEN, HELGE ABILDHAUGE; HÄLLFORS, GUY; HÄLLFORS, SEIJA; IKÄVALKO, JOHANNA (1993). "New observations on the heterotrophic protist genus Thaumatomastix (Thaumatomastigaceae, Protista incertae sedis), with particular emphasis on material from the Baltic Sea". Annales Botanici Fennici. 30 (2): 87–108. ISSN   0003-3847. JSTOR   23726281.
  6. "WoRMS - World Register of Marine Species - Thaumatomastix Lauterborn, 1899". www.marinespecies.org. Retrieved 2020-04-30.