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Trichodesmium

Generic name: TRICHODESMIUM Ehrenberg ex Gomont, 1892, nom. cons. Ann. Sci. Nat. Bot., ser. 7, 16: 193.
Synonyms:
HALIARACHNE Lemmermann, 1899. Abh. Maturw. Ver. Bremen 16: 353.
HELIOTRICHUM Wille ex Schütt, 1893. Pflanzenleben Hochsee, p. 39.
PELAGOTHRIX J. Schmidt, 1901. Vidensk. Medd. Nat. Foren. København, p. 144.
SKUJAELLA De-Toni, 1938. Diagn. Alg. nov. 1, 4: 397.
XANTHOTRICHUM Wille ex Schütt, 1893. Pflanzenleben Hochsee, p. 39.
[ TRICHODESMIUM Ehrenberg, Neue Beobachtungen uber blutartige Erscheinungen in Aegyptien, Arabien und Sibirien, in Poggendorf, Annalen der Physik und Chemie, Band XVIII p.506, 1830 ex Gomont,1892: Trichodesmium, Oscillatoria spec.]
Diagnosis:
Gomont (1892): Trichomata cylindracea, evaginata, in fasciculos squamuliformes, discretos, libere natantes muco fugacissimo aggre- gata, apice recta attenuata
leviter capitata. Cellula apicalis truncato-conica, calyptram convexam praebens.
Type species: Trichodesmium erythraeum
Ehrenberg ex Gomont 1892
Descriptions:
Komárek (1992): Filamentous, colonial, free-floating; trichomes straight or curved, unified parallely into fascicles or radially into elongated or spherical, small colonies by the help of fine, unstructured, diffluent, colourless, homogenous mucilage. Trichomes slightly motile, 6-22 um wide, at the ends sometimes attenuated up to conspicuously attenuated with elongated and hyaline terminal cells, or not attenuated, only with a rounded or narrowed terminal cell, sometimes with a calyptra, constricted
or unconstricted at the cross walls, multicelled, simple, uniserial, unbranched, without firm sheaths. Cells more or less isodiametric or slightly shorter or longer than wide, cylindrical or barrel-shaped, to the ends sometimes elongated, with plenty of aerotopes; thylakoids are irregularly coiled near the cell walls up to through the whole cell content. In Trichodesmium species were found special ecophysiological properties (valid only for marine species ?), e.g., the special type of "strong" gas vesicles, capacity for nitrogen fixation, low molecular weight of fatty acid composition. Heterocytes and akinetes are absent.
Genotype differences, molecular data:
Reproduction strategies, life cycles, cell division:
Komárek (1992): Cell division by the crosswise fission of all cells, with exception of apical ones. The cells grow into original size before the next division. Reproduction by fragmentation of trichomes into motile hormogonia by help of necridic cells and by disintegration of colonies. Hormogonia germinate at both ends (isopolar).
Ultrastructure:
Taxonomic position, higher hierarchy: Cyanophyceae,
Oscillatoriales, Phormidiaceae, Phormidioideae
Notes to taxonomy, misinterpretations:
Ecology, ecophysiology, ecological significance:
Komárek (1992): Only planktic species, from which three are freshwater (rarely occurring in large water reservoirs), the other are marine. They cause sometimes reddish water blooms in tropical seas and oceans, sometimes in lower layers (several meters under the water level).
Gomont (1892): Plantae sociales, pelagicae, innumerabili copia per aequora calidiora vagantes.
Physiology and biochemistry:
Distribution, endemism, problematic citations:
Reference strain:
Infrageneric scheme, species concept:
List of species:
freshwater species
Trichodesmium iwanoffianum Nygaard 1926
Trichodesmium lacustre Klebahn 1895

marine species
Trichodesmium clevei (J. Schmidt) Anagnostidis et Komárek 1988
Trichodesmium contortum (Wille) Wille in Brandt 1904
Trichodesmium erythraeum Ehrenberg ex Gomont 1892. Ann. Sci. Nat. Bot., ser. 7, 16: 196
Trichodesmium hildebrandtii Gomont 1892. Ann. Sci. Nat. Bot., ser. 7, 16: 197
Trichodesmium lenticulare (Lemmermann) Anagnostidis et Komárek 1988
Trichodesmium radians (Wille) Golubić 1977
Trichodesmium scoboideum Lucas 1919
Trichodesmium thiebautii Gomont ex Gomont 1892. Ann. Sci. Nat. Bot., ser. 7, 16: 197

Unclear taxa:
freshwater species
Oscillatoria lacustris var. solitaria Behre 1956
Oscillatoria lacustris forma sensu Rich 1933
Oscillatoria lacustris sensu Ley 1947
Trichodesmium contortum sensu Umezaki 1974
Trichodesmium lacustre forma sensu Hindák 1988
Trichodesmium lacustre sensu Nygaard 1977
Trichodesmium/Oscillatoria lacustris sensu G.M. Smith 1918
Trichdesmium cf. radians [solitary trichomes, Australia]

Keys:
List of stains:
Drawings:
Komárek
1992
Application technology:
Literature:

  2.1 taxonomy: Gomont 1892, Geitler 1942, Kosinskaja 1948, Sournia 1968, Umezaki 1974, Golubic 1977, Nygaard 1977, Walsby 1981, Komárek 1992
  2.2 cytomorphology:
  2.3 16S rRNA sequencing:
  2.4 biology and life cycles:
  2.5 ecology: