HOME
        TheInfoList



The Labyrinthulomycetes (ICBN) or Labyrinthulea (ICZN) are a class of protists that produce a network of filaments or tubes, which serve as tracks for the cells to glide along and absorb nutrients for them. The two main groups are the labyrinthulids (or slime nets) and thraustochytrids. They are mostly marine, commonly found as parasites on algae and seagrasses or as decomposers on dead plant material. They also include some parasites of marine invertebrates.


Characteristics


Although they are outside the cells, the filaments of Labyrinthulomycetes are surrounded by a membrane. They are formed and connected with the cytoplasm by a unique organelle called a sagenogen or bothrosome. The cells are uninucleated and typically ovoid, and move back and forth along the amorphous network at speeds varying from 5-150 μm per minute. Among the labyrinthulids, the cells are enclosed within the tubes, and among the thraustochytrids, they are attached to their sides.


Classification


Labyrinthulomycetes/Labyrinthulea used to belong to the defunct fungal phylum Labyrinthulomycota. They were originally considered unusual slime moulds, although they are not very similar to the other sorts. The structure of their zoospores and genetic studies show them to be a primitive group of heterokonts, but their classification and treatment remains somewhat unsettled. This class has usually two orders, Labyrinthulales and Thraustochytriales (ICBN), or Labyrinthulida and Thraustochytrida (ICZN), but a third has recently been proposed. * Genus ''Stellarchytrium'' FioRito & Leander 2016 * Family Oblongichytriidae Cavalier-Smith 2012 ** Genus ''Oblongichytrium'' Yokoyama & Honda 2007 * Order Labyrinthulida Doflein 1901 ** Family Aplanochytriidae Leander ex Cavalier-Smith 2012 *** Genus ''Aplanochytrium'' Bahnweg & Sparrow 1972 '[[Labyrinthuloides''_Perkins_1973.html" style="text-decoration: none;"class="mw-redirect" title="Labyrinthuloides.html" style="text-decoration: none;"class="mw-redirect" title="'[[Labyrinthuloides">'[[Labyrinthuloides'' Perkins 1973">Labyrinthuloides.html" style="text-decoration: none;"class="mw-redirect" title="'[[Labyrinthuloides">'[[Labyrinthuloides'' Perkins 1973 ** Family [[Labyrinthulidae Cienkowski 1867 *** Genus ''[[Labyrinthomyxa'' Duboscq 1921 *** Genus ''[[Pseudoplasmodium'' Molisch 1925 *** Genus ''[[Labyrinthula'' Cienkowski 1864 '[[Labyrinthodictyon''_Valkanov_1969;_''[[Labyrinthorhiza.html" style="text-decoration: none;"class="mw-redirect" title="Labyrinthodictyon.html" style="text-decoration: none;"class="mw-redirect" title="'[[Labyrinthodictyon">'[[Labyrinthodictyon'' Valkanov 1969; ''[[Labyrinthorhiza">Labyrinthodictyon.html" style="text-decoration: none;"class="mw-redirect" title="'[[Labyrinthodictyon">'[[Labyrinthodictyon'' Valkanov 1969; ''[[Labyrinthorhiza'' Chadefaud 1956] * Order [[Amphitremida Gomaa et al. 2013 ** Family [[Diplophryidae Cavalier-Smith 2012 *** Genus ''[[Diplophrys'' Barker 1868 ** Family [[Amphitrematidae Poche 1913 *** Genus ''Paramphitrema'' Valkanov 1970 *** Genus ''Archerella'' Loeblich & Tappan 1961 *** Genus ''Amphitrema'' Archer 1867 * Order Thraustochytriida Alderman & 1974 ** Genus ''Pyrrhosorus'' Juel 1901 ** Genus ''Thanatostrea'' Franc & Arvy 1969 ** Family Althorniidae Cavalier-Smith 2012 *** Genus ''Althornia'' Jones & Alderman 1972 ** Family Sorodiplophryidae Cavalier-Smith 2012 *** Genus ''Sorodiplophrys'' Olive & Dykstra 1975 ** Family Amphifilidae Cavalier-Smith 2012 *** Genus ''Amphifila'' Cavalier-Smith 2012 *** Genus ''Fibrophrys columna'' Takahashi et al. 2016 ** Family Thraustochytriidae Sparrow ex Cejp 1959 *** Genus ''Japonochytrium'' Kobayasi & Ôkubo 1953 *** Genus ''Monorhizochytrium'' Doi & Honda 2017 *** Genus ''Sicyoidochytrium'' Yokoy., Salleh & Honda 2007 *** Genus ''Aurantiochytrium'' Yokoy. & Honda 2007 *** Genus ''Ulkenia'' Gaertn. 1977 *** Genus ''Parietichytrium'' Yokoy., Salleh & Honda 2007 *** Genus ''Botryochytrium'' Yokoy., Salleh & Honda 2007 *** Genus ''Schizochytrium'' Goldst. & Belsky emend. Booth & Mill. *** Genus ''Thraustochytrium'' Sparrow 1936 *** Genus ''Hondaea'' Amato & Cagnac 2018 *** Genus ''Labyrinthulochytrium Hassett & Gradinger 2018''


Genetic code


The labyrinthulomycete ''Thraustochytrium aureum'' is notable for the alternative genetic code of its mitochondria which use as a stop codon instead of coding for Leucine. This code is represented by NCBI translation table 23, ''Thraustochytrium'' mitochondrial code.


Gallery


File:Aplanolm.jpg|''Aplanochytrium'' sp. under light microscope File:Aplanosem.png|''Aplanochytrium'' sp. under SEM File:Aurantiochytrium limacinum SR21.jpg|''Aurantiochytrium'' sp. File:Collection Penard MHNG Specimen 48-2-4 Amphitrema stenostoma.tif|Test of ''Amphitrema'', a testate amoeba recently included in the group File:Tsenkovsky Lev Semyonovich.jpg|Leon Cienkowski, polish botanist who in 1867 described ''Labyrinthula'', the first genus of the groupCienkowski, L. (1867). Ueber den Bau und die Entwicklung der Labyrinthuleen. ''Arch. mikr. Anat.'', 3:274




References





External links



Labyrinthulomycota
{{Taxonbar|from1=Q1148791|from2=Q16653009 Category:Heterokont classes Category:Bigyra