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Cyclodictyon
From Williams et al., 2017:
[Cyclodictyon, Cookson and Eisenack, 1958, p. 58
Acritarch genus.
Type Species: Cyclodictyon paradoxum, Cookson and Eisenack, 1958
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Original description: [Cookson and Eisenack, 1958]:
Description:
Microfossil consisting of a spherical or oval shell and a hollow-domed equatorially attached network.
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Modified description:
Stover and Evitt, 1978, p. 34-35:
Synopsis:
Cysts holocavate, subspherical; endocyst small relative to surrounding reticulate pericyst; supporting strands extend between the separated wall layers near the poles; archeopyle apical, type uncertain.
Description:
Shape: Subspherical.
Wall relationships: Cysts holocavate, pericoel entire; endocyst considerably smaller than pericyst.
Wall features: Endophragm smooth; periphragm reticulate; curved supporting strands, which are broad, smooth, entire, or (occasionally) branched, extend between wall layers near ends of the endocyst.
Paratabulation: None clearly indicated.
Archeopyle: Apical, type uncertain; operculum not observed.
Paracingulum: Not indicated.
Parasulcus: Not indicated.
Size: Intermediate.
Affinities:
Cyclodictyon differs from Membranilarnacia in having a reticulate periphragm rather than a smooth, thin, commonly folded periphragm. In addition, the endocyst of Cyclodictyon is small relative to the pericyst, whereas in Membranilarnacia the endocyst is large in proportion to the pericyst.
[Cyclodictyon, Cookson and Eisenack, 1958, p. 58
Acritarch genus.
Type Species: Cyclodictyon paradoxum, Cookson and Eisenack, 1958
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Cookson and Eisenack, 1958]:
Description:
Microfossil consisting of a spherical or oval shell and a hollow-domed equatorially attached network.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Modified description:
Stover and Evitt, 1978, p. 34-35:
Synopsis:
Cysts holocavate, subspherical; endocyst small relative to surrounding reticulate pericyst; supporting strands extend between the separated wall layers near the poles; archeopyle apical, type uncertain.
Description:
Shape: Subspherical.
Wall relationships: Cysts holocavate, pericoel entire; endocyst considerably smaller than pericyst.
Wall features: Endophragm smooth; periphragm reticulate; curved supporting strands, which are broad, smooth, entire, or (occasionally) branched, extend between wall layers near ends of the endocyst.
Paratabulation: None clearly indicated.
Archeopyle: Apical, type uncertain; operculum not observed.
Paracingulum: Not indicated.
Parasulcus: Not indicated.
Size: Intermediate.
Affinities:
Cyclodictyon differs from Membranilarnacia in having a reticulate periphragm rather than a smooth, thin, commonly folded periphragm. In addition, the endocyst of Cyclodictyon is small relative to the pericyst, whereas in Membranilarnacia the endocyst is large in proportion to the pericyst.