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Cirrusphaera
From Fensome et al., 2019:
Cirrusphaera, Monteil, 1992a, p.277.
Type: Monteil, 1992a, pl.2, figs.1–9, as Cirrusphaera dissimilis.
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Original description: [Monteil, 1992]: (Translation: LPP)
Synopsis:
Cyst chorate, acavate, subspherical. Processes organised in annular complexes, distally connected by a ring-trabeculum. Presence of trabecular connections between complexes. Paracingular processes typically connected by an equatorial trabeculum. Paratabulation probably of gonyaulacoid type.
Archaeopyle apical, type (tA). Opercular piece free.
Diagnosis:
Shape: Cyst chorate, acavate, subspherical.
Wall structure: Autophragm only.
Wall features: penitabular processes organised in complexes, rising from annular or straight septa. complex formed by about ten processes distally interconnected by trabeculae. Presence of trabecular interconnections between the complexes. Surface between processes smooth to granulate.
Archaeopyle: Apical, type (tA). Opercular piece free.
Paratabulation: Indicated by the archaeopyle margin and the process complexes. Formula not yet elucidated, but probably of gonyaulacoid type.
Paracingulum: Indicated by an transverse alignment of processes. Paracingular processes interconnected by an equatorial trabeculum, isolated or rarely connected with the complexes of the precingular and postcingular series.
Parasulcus: not observed.
Size: small, 45-50 µm wide.
Affinities:
Systematophora possesses annular-arched process complexes which do not develop distal trabeculae. Stiphrosphaeridium, Emmetrocysta and Adnatosphaeridium do not possess paracingular processes. Hystrichosphaerina shows distal trabecular rings, but no connections between processes and process complexes. Polystephanephorus does not possess the equatorial ring-trabeculum typical of cirrusphaera.
Cirrusphaera, Monteil, 1992a, p.277.
Type: Monteil, 1992a, pl.2, figs.1–9, as Cirrusphaera dissimilis.
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Original description: [Monteil, 1992]: (Translation: LPP)
Synopsis:
Cyst chorate, acavate, subspherical. Processes organised in annular complexes, distally connected by a ring-trabeculum. Presence of trabecular connections between complexes. Paracingular processes typically connected by an equatorial trabeculum. Paratabulation probably of gonyaulacoid type.
Archaeopyle apical, type (tA). Opercular piece free.
Diagnosis:
Shape: Cyst chorate, acavate, subspherical.
Wall structure: Autophragm only.
Wall features: penitabular processes organised in complexes, rising from annular or straight septa. complex formed by about ten processes distally interconnected by trabeculae. Presence of trabecular interconnections between the complexes. Surface between processes smooth to granulate.
Archaeopyle: Apical, type (tA). Opercular piece free.
Paratabulation: Indicated by the archaeopyle margin and the process complexes. Formula not yet elucidated, but probably of gonyaulacoid type.
Paracingulum: Indicated by an transverse alignment of processes. Paracingular processes interconnected by an equatorial trabeculum, isolated or rarely connected with the complexes of the precingular and postcingular series.
Parasulcus: not observed.
Size: small, 45-50 µm wide.
Affinities:
Systematophora possesses annular-arched process complexes which do not develop distal trabeculae. Stiphrosphaeridium, Emmetrocysta and Adnatosphaeridium do not possess paracingular processes. Hystrichosphaerina shows distal trabecular rings, but no connections between processes and process complexes. Polystephanephorus does not possess the equatorial ring-trabeculum typical of cirrusphaera.