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Spiniferopsis
From Williams et al., 2017:
[Spiniferopsis, He Cheng-quan, 1984, p. 770, 773–774
Type species: Spiniferopsis granulata, He Cheng-quan, 1984 (pl.1, fig.1)]
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Original description: [He Cheng-quan, 1984]:
Diagnosis:
Cysts skolochorate. Body subspherical to ellipsoidal in outline, with solid, isolated processes arising from the points of junctions of sutural ridges, distally simple or branched. Processes arranged basically along cingulum and polar regions, like those of the genus Spiniferites in distribution, but without intergonal processes.
Paratabulation gonyaulacacean, appearing to be ?` (probably 4`), 0-la, 6", 6c, 5n`-(6```?), ?p, 1```` in formula; paraplate boundaries (including cingulum) indicated by low, smooth sutural ridges and gonal processes.
Cingulum clear, relatively narrow, nearly planar or slightly spiral. Shell wall moderately thick (ca. 2.5 μm) and composed of two layers; periphragm surface densely granulate.
Archaeopyle apical. Type (tA), principal suture zigzag; operculum lost.
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Modified description:
Chen et al., 1988, p. 29-30:
Synopsis:
Cysts skolochorate, body subspherical with relatively few, solid, gonal processes along the paracingulum and near the antapical pole; paratabulation possibly gonyaulacalean, indicated by parasutural ridges and processes; archeopyle apical, operculum free.
Description:
Shape: Body subspherical.
Wall relationships: Periphragm and endophragm appressed.
Wall features: Parasutural ridges low; gonal processes solid, distally simple or branched, relatively few, confined to the cingular area near the antapical end of cyst; surface between processes granular; intergonal processes absent.
Archeopyle: Apical, type [tA]; operculum free, but not observed.
Paratabulation: Indicated mainly by parasutural features, stated as gonyaulacacean, formula given as: ?`, 0-1a, 6", 6c, 5-6```?, ?p, 1````; presence of intercalary paraplates not evident.
Paracingulum: Apparently relatively narrow, planar or slightly helicoidal.
Parasulcus: Not indicated.
Size: Intermediate, 50 μm long (without operculum), 55 μm wide.
Affinities:
According to He Cheng-quan, 1984, Spiniferopsis differs from Ctenidodinium Deflandre, 1938 emend. Benson, 1985, and from Spiniferites Mantell, 1850 emend. Sarjeant, 1970, in possessing an apical archeopyle rather than an epicystal or a precingular archeopyle, respectively. Meiourogonyaulax Sarjeant in Davey et al., 1966, which has an apical archeopyle, differs from Spiniferopsis in lacking processes.
N.B. The genus is based on only one specimen.
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GSC: (GSC provisional translation: courtesy R. Fensome):
Cysts contracted or spiniform; body subspherical to ellipsoidal. Walls of medium thickness and composed of two layers. Paratabulation is gonyaulacacean, being more or less ?`(possibly 4`), 0-1a, 6``, 6c, 5``` (6```?), ?p, 1````. Plate boundaries indicated by low, smooth sutural ridges. Plates have gonal processes. Processes discrete, solid; distal poles simple or with fairly long branches. No processes observed on intergonal sutures. Cingulum normally present. Archaeopyle apical, type tA.
Comparison:
In terms of tabulation and archaeopyle, the new genus basically resembles Meiourogonyaulax. The former, however, has weak sutural ridges and longer gonal processes, while the latter has proximate, compressed cysts and developed sutural ridges which appear septate. Its apical archaeopyle distinguishes the new genus from Ctenidodinium (combination archaeopyle) and Spiniferites (precingular archaeopyle).
[Spiniferopsis, He Cheng-quan, 1984, p. 770, 773–774
Type species: Spiniferopsis granulata, He Cheng-quan, 1984 (pl.1, fig.1)]
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Original description: [He Cheng-quan, 1984]:
Diagnosis:
Cysts skolochorate. Body subspherical to ellipsoidal in outline, with solid, isolated processes arising from the points of junctions of sutural ridges, distally simple or branched. Processes arranged basically along cingulum and polar regions, like those of the genus Spiniferites in distribution, but without intergonal processes.
Paratabulation gonyaulacacean, appearing to be ?` (probably 4`), 0-la, 6", 6c, 5n`-(6```?), ?p, 1```` in formula; paraplate boundaries (including cingulum) indicated by low, smooth sutural ridges and gonal processes.
Cingulum clear, relatively narrow, nearly planar or slightly spiral. Shell wall moderately thick (ca. 2.5 μm) and composed of two layers; periphragm surface densely granulate.
Archaeopyle apical. Type (tA), principal suture zigzag; operculum lost.
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Modified description:
Chen et al., 1988, p. 29-30:
Synopsis:
Cysts skolochorate, body subspherical with relatively few, solid, gonal processes along the paracingulum and near the antapical pole; paratabulation possibly gonyaulacalean, indicated by parasutural ridges and processes; archeopyle apical, operculum free.
Description:
Shape: Body subspherical.
Wall relationships: Periphragm and endophragm appressed.
Wall features: Parasutural ridges low; gonal processes solid, distally simple or branched, relatively few, confined to the cingular area near the antapical end of cyst; surface between processes granular; intergonal processes absent.
Archeopyle: Apical, type [tA]; operculum free, but not observed.
Paratabulation: Indicated mainly by parasutural features, stated as gonyaulacacean, formula given as: ?`, 0-1a, 6", 6c, 5-6```?, ?p, 1````; presence of intercalary paraplates not evident.
Paracingulum: Apparently relatively narrow, planar or slightly helicoidal.
Parasulcus: Not indicated.
Size: Intermediate, 50 μm long (without operculum), 55 μm wide.
Affinities:
According to He Cheng-quan, 1984, Spiniferopsis differs from Ctenidodinium Deflandre, 1938 emend. Benson, 1985, and from Spiniferites Mantell, 1850 emend. Sarjeant, 1970, in possessing an apical archeopyle rather than an epicystal or a precingular archeopyle, respectively. Meiourogonyaulax Sarjeant in Davey et al., 1966, which has an apical archeopyle, differs from Spiniferopsis in lacking processes.
N.B. The genus is based on only one specimen.
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GSC: (GSC provisional translation: courtesy R. Fensome):
Cysts contracted or spiniform; body subspherical to ellipsoidal. Walls of medium thickness and composed of two layers. Paratabulation is gonyaulacacean, being more or less ?`(possibly 4`), 0-1a, 6``, 6c, 5``` (6```?), ?p, 1````. Plate boundaries indicated by low, smooth sutural ridges. Plates have gonal processes. Processes discrete, solid; distal poles simple or with fairly long branches. No processes observed on intergonal sutures. Cingulum normally present. Archaeopyle apical, type tA.
Comparison:
In terms of tabulation and archaeopyle, the new genus basically resembles Meiourogonyaulax. The former, however, has weak sutural ridges and longer gonal processes, while the latter has proximate, compressed cysts and developed sutural ridges which appear septate. Its apical archaeopyle distinguishes the new genus from Ctenidodinium (combination archaeopyle) and Spiniferites (precingular archaeopyle).