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Pluriarvalium
From Fensome et al., 2019:
Pluriarvalium, Sarjeant, 1962b, p.260.
Taxonomic senior synonym: Pareodinia, according to Wiggins (1975, p.102) -- however, Stover and Evitt (1978, p.119) retained Pluriarvalium. Type: Sarjeant, 1962b, pl.1, fig.5, as Pluriarvalium osmingtonense.
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Original description: [Sarjeant, 1962]:
Description:
Dinoflagellates of globular to oval shape, with distinct transverse and longitudinal furrows, the latter extending across the epitheca on to the hypotheca, and with an apical horn.
Tabulation: up to five apical plates, one to three anterior intercalary plates, six pre-equatorial plates, six post-equatorial plates, one posterior intercalary plate, one posterior ventral plate corresponding in position to the posterior extension of the longitudinal furrow, and a single antapical plate partially or completely surrounded by a posterior circle of small plates.
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Modified description:
Stover and Evitt, 1978, p. 119:
Synopsis:
Cysts proximate, ellipsoidal, with an apical horn; paratabulation indicated by low to moderately high parasutural ridges delimiting numerous preapical and posterior intercalary paraplates in addition to precingular, paracingular, and postcingular paraplates; archeopyle intercalary, Type I or 3I.
Description:
Shape: Ellipsoidal with a slender short apical horn.
Wall Relationship: Autophragm only; surrounding amorphous cloak, which may or may not be preserved, is not considered a wall layer.
Wall Features: Parasutural ridges low to moderately high; crests smooth, enticulate, setate or fimbriate. Surface between parasutural ridges smooth or with features of low relief.
Paratabulation: Indicated by parasutural features; formula: 7pr, 6`, 5-6a, 5-6", 2-7c, 7"`, 3"", and an uncertain number of posterior intercalary and sulcal paraplates. Paratabulation not known to be expressed completely on a single specimen.
Archeopyle: Intercalary, either Type I or 3I; operculum free.
Paracingulum: Indicated by from two to seven cingular paraplates, or by transverse parallel parasutural ridges alone.
Parasulcus: Longitudinally elongate area, wider antapically than apically, confined mainly to hypocyst; may contain paraplates, exact number uncertain.
Size: Intermediate.
Affinities:
Pluriarvalium differs from Paragonyaulacysta in having numerous preapical and posterior intercalary paraplates in addition to precingular, paracingular, and postcingular ones. Pareodinia lacks indications of paratabulation other than archeopyle.
Pluriarvalium, Sarjeant, 1962b, p.260.
Taxonomic senior synonym: Pareodinia, according to Wiggins (1975, p.102) -- however, Stover and Evitt (1978, p.119) retained Pluriarvalium. Type: Sarjeant, 1962b, pl.1, fig.5, as Pluriarvalium osmingtonense.
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Sarjeant, 1962]:
Description:
Dinoflagellates of globular to oval shape, with distinct transverse and longitudinal furrows, the latter extending across the epitheca on to the hypotheca, and with an apical horn.
Tabulation: up to five apical plates, one to three anterior intercalary plates, six pre-equatorial plates, six post-equatorial plates, one posterior intercalary plate, one posterior ventral plate corresponding in position to the posterior extension of the longitudinal furrow, and a single antapical plate partially or completely surrounded by a posterior circle of small plates.
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Modified description:
Stover and Evitt, 1978, p. 119:
Synopsis:
Cysts proximate, ellipsoidal, with an apical horn; paratabulation indicated by low to moderately high parasutural ridges delimiting numerous preapical and posterior intercalary paraplates in addition to precingular, paracingular, and postcingular paraplates; archeopyle intercalary, Type I or 3I.
Description:
Shape: Ellipsoidal with a slender short apical horn.
Wall Relationship: Autophragm only; surrounding amorphous cloak, which may or may not be preserved, is not considered a wall layer.
Wall Features: Parasutural ridges low to moderately high; crests smooth, enticulate, setate or fimbriate. Surface between parasutural ridges smooth or with features of low relief.
Paratabulation: Indicated by parasutural features; formula: 7pr, 6`, 5-6a, 5-6", 2-7c, 7"`, 3"", and an uncertain number of posterior intercalary and sulcal paraplates. Paratabulation not known to be expressed completely on a single specimen.
Archeopyle: Intercalary, either Type I or 3I; operculum free.
Paracingulum: Indicated by from two to seven cingular paraplates, or by transverse parallel parasutural ridges alone.
Parasulcus: Longitudinally elongate area, wider antapically than apically, confined mainly to hypocyst; may contain paraplates, exact number uncertain.
Size: Intermediate.
Affinities:
Pluriarvalium differs from Paragonyaulacysta in having numerous preapical and posterior intercalary paraplates in addition to precingular, paracingular, and postcingular ones. Pareodinia lacks indications of paratabulation other than archeopyle.