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Pascherinema

Generic name: PASCHERINEMA de Toni, 1936. Noter. Nomencl. Algol. 8: 5.
Synonyms: ENDONEMA Pascher, 1929; Jahrb. wiss. Bot. 70: 347.
Diagnosis:
Type species: Pascherinema moniliforme (Pascher) de Toni 1936
Descriptions:
Komárek & Anagnostidis (1998): Pseudofilaments of «connected» cells solitary, uniseriate, more or less cylindrical, heteropolar, more or less erect, without wide mucilaginous envelopes, attached by one end (with modified basal, usually ovoid cell with narrowed basal stipe) to the substrate. Cells in pseudofilaments more or less of the same size and shape, rounded or barrel-shaped (causing the moniliform appearance of pseudofilaments), only the basal cell is modified and the terminal cell(s) slightly enlarged and usually elongate-rounded, but not exceeding distinctly the pseudofilament width. Around cells narrow, firm sheaths, visible only during cell division or after baeocyte liberation.
Komárek (1992): Pseudofilamentous; pseudofilaments solitary, isolated, moniliform, uniserial, heteropolar, composed from more or less elongated basal cells joined to the substrate by narrow and shortly elongated end, and from a row of spherical, barrel-shaped or obovate cells, which arise probably by the successive and repeated crosswise cell division; apical cell usually elongated, cylindrical and rounded. Without gelatinous sheath, but at the apex, where the cells divide into nanocytes (7), occurs very narrow, firm, colourless sheath. Cells with pale blue-green content.
Genotype differences, molecular data:
Reproduction strategies, life cycles, cell division:
Komárek & Anagnostidis (1998):Cell division transversely to the pseudofilament axis, or (mainly from enlarged terminal cells) successively into few or several (2-16) oval or spherical, motile baeocytes. Reproduction by means of baeocytes. Little known genus, never found again for about 70 years, needs revision.
Komárek (1992): Cell divide in pseudofilaments by the repeated crosswise fission and grow before the next division into the original size. Apical enlarged cells divide sometimes successively in 2-16 nanocytes, which escape from the thin, firm sheath, opened at the apex (real sporangia 7; sheaths are not visible in pseudofilaments). Nanocytes are motile, join to the substrate and change in a new basal cell, which start to divide crosswise in the upper part. One nanocyte remains sometimes joined to the pseudofilament and grows into normal vegetative cell.
Ultrastructure:
Taxonomic position, higher hierarchy:
Cyanophyceae, Chroococcales, Hyellaceae, Pascherinematoideae
Notes to taxonomy, misinterpretations:
Ecology, ecophysiology, ecological significance:
Komárek (1992): Both species distinguish in dimensions and slightly in cell form, and grow epiphytically on leaves on Sphagnum, or Potamogeton; described from Czechoslovakia (Bohemia). Not found after description, very problematical genus with strange morphology in cyanophytes (revision is needed; according to Drouet et Daily 1956 = fungi).
Physiology and biochemistry:
Distribution, endemism, problematic citations:
Reference strain:
Infrageneric scheme, species concept:
List of species:
Pascherinema gracile (Pascher) de Toni 1936
Pascherinema moniliforme (Pascher) de Toni 1936
Keys:
List of stains:
Drawings:
Komárek 1992
Application technology:
Literature:
  2.1 taxonomy: Pascher 1929, De-Toni 1936, Geitler 1932, Geitler 1942, Villeret 1953, Bourrelly 1966, Starmach 1966, Bourrelly 1970, Bourrelly 1985, Komárek 1992, Komárek &
Anagnostidis 1998
  2.2 cytomorphology:
  2.3 16S rRNA sequencing:
  2.4 biology and life cycles:
  2.5 ecology: