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Pentadinium
From Williams et al., 2017:
[Pentadinium, Gerlach, 1961, p. 164–165; Emendation: Benedek et al., 1982, p. 266–268.
Type species: Pentadinium laticinctum, Gerlach, 1961 (pl.26, figs.5–6; text-figs.6–7)] ; emend. Benedek et al., 1982
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Original description: [Gerlach, 1961]: (Translation: Stover and Evitt, 1978, p. 179-180):
Diagnosis:
Theca spherical to polyhedral. Shell always with an oval or spherical inner body, wall tabulate: 5``, 5``` and 1````. Number of apical plates 1`(?). Girdle helicoidal; longitudinal furrow between the displaced extremities of the girdle. External shell delicate, inner capsule robust.
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Modified description:
Stover and Evitt 1978 p. 179-180:
Synopsis:
Cysts proximochorate, cavate; body subspherical to subpolyhedral; paratabulation gonyaulacacean, expressed incompletely by folds in periphragm; archeopyle precingular, Type P.
Description:
Shape: Subspherical to subpolyhedral; outline in apical-antapical view subcircular; slight preference for apical-antapical orientation.
Wall relationships: Cysts cavate, endocyst subspherical; periphragm and endophragm appressed between former`s generally wide parasutural folds.
Wall features: Parasutural folds on epicyst and pericyst normally underlain by narrow pericoels; folds may have process-like appearance in optical view. Surface of endophragm scabrate, granulate, or vermiculate; periphragm smooth or faintly ornamented.
Paratabulation: Indicated incompletely by parasutural folds; gonyaulacacean, formula: 2`, 5``, Xc, 4-5```, 0-1p, 1````. Small number of paraplates reflects reduced expression of paratabulation on ventral surface; those paraplates never indicated, or typically not seen are 1`, 4`, 6``, 1```, 6```, and 1p.
Archeopyle: Precingular, Type P (3`` only); perioperculum and endoperculum appressed apically, separated antapically.
Paracingulum: Indicated by pronounced cavate equatorial extension of periphragm.
Parasulcus: Position indicated by the interruption of the paracingulum, otherwise poorly expressed.
Size: Intermediate to large.
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Emended description:
Benedek et al., 1982:
Diagnosis:
Cyst proximate to proximochorate, spherical to subspherical or subpolyhedral and typically as broad as it is long. Apical, antapical and lateral horns are lacking. Phragma composed of two layers, in general contact but typically separating along he cingulum and along paraplate boundaries (suturocavate). Paratabulation 4`, 0a, 6``, ?5-6c, 5```, 1p, 0-1pv, 1````; the boundaries between apical paraplates and between ventral paraplates and the sulcus may be incompletely expressed. archaeopyle single-plated precingular (Type P), formed by the loss of the third precingular paraplate.
Affinities:
Pentadinium differs from Stephodinium in that its periphragm and endophragm are normally appressed between parasutural features, except along the paracingulum. In Stephodinium, the periphragm and endophragm are widely separated dorsally.
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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.
Pentadinium Gerlach, 1961, emend. Benedek et al., 1982. Benedek et al. (1982, p.267) emended the diagnosis as follows. Cyst proximate to proximochorate, spherical to subspherical or subpolyhedral and typically as broad as it is long. Apical, antapical and lateral horns are lacking. Phragma composed of two layers, in general contact but typically separating along the cingulum and along paraplate boundaries (suturocavate). Paratabulation 4`, 0a, 6", ?5-6c, 5``` , 1p, 0-1pv, 1```` ; the boundaries between apical paraplates and between ventral paraplates and the sulcus may be incompletely expressed. Archeopyle single-plate precingular (type P), formed by loss of the third precingular paraplate.
[Pentadinium, Gerlach, 1961, p. 164–165; Emendation: Benedek et al., 1982, p. 266–268.
Type species: Pentadinium laticinctum, Gerlach, 1961 (pl.26, figs.5–6; text-figs.6–7)] ; emend. Benedek et al., 1982
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Original description: [Gerlach, 1961]: (Translation: Stover and Evitt, 1978, p. 179-180):
Diagnosis:
Theca spherical to polyhedral. Shell always with an oval or spherical inner body, wall tabulate: 5``, 5``` and 1````. Number of apical plates 1`(?). Girdle helicoidal; longitudinal furrow between the displaced extremities of the girdle. External shell delicate, inner capsule robust.
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Modified description:
Stover and Evitt 1978 p. 179-180:
Synopsis:
Cysts proximochorate, cavate; body subspherical to subpolyhedral; paratabulation gonyaulacacean, expressed incompletely by folds in periphragm; archeopyle precingular, Type P.
Description:
Shape: Subspherical to subpolyhedral; outline in apical-antapical view subcircular; slight preference for apical-antapical orientation.
Wall relationships: Cysts cavate, endocyst subspherical; periphragm and endophragm appressed between former`s generally wide parasutural folds.
Wall features: Parasutural folds on epicyst and pericyst normally underlain by narrow pericoels; folds may have process-like appearance in optical view. Surface of endophragm scabrate, granulate, or vermiculate; periphragm smooth or faintly ornamented.
Paratabulation: Indicated incompletely by parasutural folds; gonyaulacacean, formula: 2`, 5``, Xc, 4-5```, 0-1p, 1````. Small number of paraplates reflects reduced expression of paratabulation on ventral surface; those paraplates never indicated, or typically not seen are 1`, 4`, 6``, 1```, 6```, and 1p.
Archeopyle: Precingular, Type P (3`` only); perioperculum and endoperculum appressed apically, separated antapically.
Paracingulum: Indicated by pronounced cavate equatorial extension of periphragm.
Parasulcus: Position indicated by the interruption of the paracingulum, otherwise poorly expressed.
Size: Intermediate to large.
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Emended description:
Benedek et al., 1982:
Diagnosis:
Cyst proximate to proximochorate, spherical to subspherical or subpolyhedral and typically as broad as it is long. Apical, antapical and lateral horns are lacking. Phragma composed of two layers, in general contact but typically separating along he cingulum and along paraplate boundaries (suturocavate). Paratabulation 4`, 0a, 6``, ?5-6c, 5```, 1p, 0-1pv, 1````; the boundaries between apical paraplates and between ventral paraplates and the sulcus may be incompletely expressed. archaeopyle single-plated precingular (Type P), formed by the loss of the third precingular paraplate.
Affinities:
Pentadinium differs from Stephodinium in that its periphragm and endophragm are normally appressed between parasutural features, except along the paracingulum. In Stephodinium, the periphragm and endophragm are widely separated dorsally.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Pentadinium Gerlach, 1961, emend. Benedek et al., 1982. Benedek et al. (1982, p.267) emended the diagnosis as follows. Cyst proximate to proximochorate, spherical to subspherical or subpolyhedral and typically as broad as it is long. Apical, antapical and lateral horns are lacking. Phragma composed of two layers, in general contact but typically separating along the cingulum and along paraplate boundaries (suturocavate). Paratabulation 4`, 0a, 6", ?5-6c, 5``` , 1p, 0-1pv, 1```` ; the boundaries between apical paraplates and between ventral paraplates and the sulcus may be incompletely expressed. Archeopyle single-plate precingular (type P), formed by loss of the third precingular paraplate.