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Ochetodinium
From Williams et al., 2017:
[Ochetodinium, Damassa, 1979a, p. 830, 833
Type species: Ochetodinium romanum, Damassa, 1979a (pl.6, figs.1, 5)]
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Original description: [Damassa, 1979]:
Description:
Chorate cyst, spherical to ellipsoidal in shape, paratabulation indicated by parasutural elevations of the outer part of the wall that are not simple septa.
Intratabular ornamentation also developed.
Archeopyle precingular, Type P, formed by loss of the third precingular paraplate.
Wall consisting only of autophragm, generally spongy in appearance. Gonyaulacacean paratabulation essentially complete, formula: 4`, 6", 6c, xs, 1p, 6```,1````. Paracingulum and parasulcus indicated by parasutural ornamentation. Small paraplates on ventral surface indistinct.
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Modified description:
Stover and Williams, 1987, p. 165:
Synopsis:
Cysts proximate, subspherical; paratabulation indicated by parasutural features, formula: 4`, 6", Xc, 6```, 1 p, 1```` and 1 or more s; paraplates arranged in the Leptodinium pattern; surface between parasutural features ornamented; archeopyle precingular, type P, operculum free.
Description:
Shape: Subspherical.
Wall relationships: Undifferentiated autocyst only.
Wall Features: Parasutural septa of approximately uniform height; areas between septa ornamented.
Archeopyle: Precingular, type P (3" only), may be enlarged; operculum free.
Paratabulation: Indicated by parasutural features; gonyaulacacean, formula: 4`, 6", Xc, 6```, 1 p, 1````, 1-?s. Paraplate configuration like that on Leptodinium with characteristic pentagonal paraplate 6" in substantial contact with paraplate 1 `; hypocyst sexiform.
Paracingulum: Indicated by parallel, transverse, equatorial septa; area between septa may be unornamented.
Parasulcus: Indicated by bordering parasutural septa; posterior sulcal paraplate differentiated, others indistinct.
Size: Small to intermediate, diameter about 45 to 75 µm.
Affinities:
Ochetodinium differs from Leptodinium Klement 1960 emended Sarjeant 1982 in having the areas between septa conspicuously ornamented except for the paracingulum and parasulcus.
[Ochetodinium, Damassa, 1979a, p. 830, 833
Type species: Ochetodinium romanum, Damassa, 1979a (pl.6, figs.1, 5)]
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Original description: [Damassa, 1979]:
Description:
Chorate cyst, spherical to ellipsoidal in shape, paratabulation indicated by parasutural elevations of the outer part of the wall that are not simple septa.
Intratabular ornamentation also developed.
Archeopyle precingular, Type P, formed by loss of the third precingular paraplate.
Wall consisting only of autophragm, generally spongy in appearance. Gonyaulacacean paratabulation essentially complete, formula: 4`, 6", 6c, xs, 1p, 6```,1````. Paracingulum and parasulcus indicated by parasutural ornamentation. Small paraplates on ventral surface indistinct.
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Modified description:
Stover and Williams, 1987, p. 165:
Synopsis:
Cysts proximate, subspherical; paratabulation indicated by parasutural features, formula: 4`, 6", Xc, 6```, 1 p, 1```` and 1 or more s; paraplates arranged in the Leptodinium pattern; surface between parasutural features ornamented; archeopyle precingular, type P, operculum free.
Description:
Shape: Subspherical.
Wall relationships: Undifferentiated autocyst only.
Wall Features: Parasutural septa of approximately uniform height; areas between septa ornamented.
Archeopyle: Precingular, type P (3" only), may be enlarged; operculum free.
Paratabulation: Indicated by parasutural features; gonyaulacacean, formula: 4`, 6", Xc, 6```, 1 p, 1````, 1-?s. Paraplate configuration like that on Leptodinium with characteristic pentagonal paraplate 6" in substantial contact with paraplate 1 `; hypocyst sexiform.
Paracingulum: Indicated by parallel, transverse, equatorial septa; area between septa may be unornamented.
Parasulcus: Indicated by bordering parasutural septa; posterior sulcal paraplate differentiated, others indistinct.
Size: Small to intermediate, diameter about 45 to 75 µm.
Affinities:
Ochetodinium differs from Leptodinium Klement 1960 emended Sarjeant 1982 in having the areas between septa conspicuously ornamented except for the paracingulum and parasulcus.