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Cerebrocysta
From Williams et al., 2017:
[Cerebrocysta, Bujak in Bujak, 1980, p. 42; Emendation: Stover and Williams, 1987, p. 57
Type species: Cerebrocysta bartonensis, Bujak in Bujak et al., 1980 (pl.13, figs.4–5)]
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Original description: [Bujak, 1980]:
Diagnosis:
Autocyst spherical to ovoidal, without apical, antapical, or other projections, except for an apparently random ornament of low crests. The crests occasionally suggest a paratabular arrangement. The archaeopyle is formed by the loss of one (3") or more precingular paraplates.
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Emended description:
Stover and Williams, 1987:
Synopsis:
Cysts proximate, subspherical; autophragm ornamented with relatively short, curved or straight, discontinuous ridges and interspersed low granules; placement of ridges occasionally suggests paratabulation; archeopyle precingular, simple or compound, P to 3P, (3" to 2"-4"); opercular piece(s) free.
Description:
Shape: Subspherical.
Wall relationships: Autophragm only.
Wall features: No clearly evident parasutural features. Surface ornamented with relatively short, curved or straight, discontinuous ridges and interspersed low, discrete, granules.
Archeopyle: Precingular, simple or compound, types P to 3P (3" to 2"-4"), opercular piece(s) free; on forms having compound opercula it is not known whether released paraplates remain together or separate.
Paratabulation: Generally not indicated. Suggestions of paratabulation may be occasionally discernible.
Paracingulum: Not indicated.
Parasulcus: Not indicated.
Size: Small, average diameter 25 µm, maximum diameter about 35 µm.
Affinities:
Cerebrocysta differs from Pyxidinposis Habib 1976 in having discontinuous ridges and isolated granules rather than being rebculate. In addition, similarly ornamented forms having different archeopyle types are included in Cerebrocysta whereas only forms with a simple precingular (type P) archeopyle are currently assigned to Pyxidinopsis. An ornamentation pattern like that described for Cerebrocysta has been observed on undescribed specimens of Elytrocysta Stover and Evitt 1978. However, these forms have an ectophragm covering the ornamentation.
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Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Cerebrocysta Bujak in Bujak et al., 1980. Stover and Williams (1987, p.57) gave the following synopsis: Cysts proximate, subspherical; autophragm ornamented with relatively short, curved or straight, discontinuous ridges and interspersed low granules; placement of ridges occasionally suggests paratabulation; archeopyle precingular, simple or compound, P to 3P, (3" to 2"-4"), opercular pieces free.
[Cerebrocysta, Bujak in Bujak, 1980, p. 42; Emendation: Stover and Williams, 1987, p. 57
Type species: Cerebrocysta bartonensis, Bujak in Bujak et al., 1980 (pl.13, figs.4–5)]
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Original description: [Bujak, 1980]:
Diagnosis:
Autocyst spherical to ovoidal, without apical, antapical, or other projections, except for an apparently random ornament of low crests. The crests occasionally suggest a paratabular arrangement. The archaeopyle is formed by the loss of one (3") or more precingular paraplates.
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Emended description:
Stover and Williams, 1987:
Synopsis:
Cysts proximate, subspherical; autophragm ornamented with relatively short, curved or straight, discontinuous ridges and interspersed low granules; placement of ridges occasionally suggests paratabulation; archeopyle precingular, simple or compound, P to 3P, (3" to 2"-4"); opercular piece(s) free.
Description:
Shape: Subspherical.
Wall relationships: Autophragm only.
Wall features: No clearly evident parasutural features. Surface ornamented with relatively short, curved or straight, discontinuous ridges and interspersed low, discrete, granules.
Archeopyle: Precingular, simple or compound, types P to 3P (3" to 2"-4"), opercular piece(s) free; on forms having compound opercula it is not known whether released paraplates remain together or separate.
Paratabulation: Generally not indicated. Suggestions of paratabulation may be occasionally discernible.
Paracingulum: Not indicated.
Parasulcus: Not indicated.
Size: Small, average diameter 25 µm, maximum diameter about 35 µm.
Affinities:
Cerebrocysta differs from Pyxidinposis Habib 1976 in having discontinuous ridges and isolated granules rather than being rebculate. In addition, similarly ornamented forms having different archeopyle types are included in Cerebrocysta whereas only forms with a simple precingular (type P) archeopyle are currently assigned to Pyxidinopsis. An ornamentation pattern like that described for Cerebrocysta has been observed on undescribed specimens of Elytrocysta Stover and Evitt 1978. However, these forms have an ectophragm covering the ornamentation.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Cerebrocysta Bujak in Bujak et al., 1980. Stover and Williams (1987, p.57) gave the following synopsis: Cysts proximate, subspherical; autophragm ornamented with relatively short, curved or straight, discontinuous ridges and interspersed low granules; placement of ridges occasionally suggests paratabulation; archeopyle precingular, simple or compound, P to 3P, (3" to 2"-4"), opercular pieces free.