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Cleistosphaeridium spissum
Cleistosphaeridium spissum, McIntyre and Brideaux, 1980
Now Prolixosphaeridium?. Originally Cleistosphaeridium, subsequently (and now) Prolixosphaeridium?.
Holotype: McIntyre and Brideaux, 1980, pl.7, fig.1-4
Locus typicus: "Grizzly Gorge", District of Mackenzie, Canada
Stratum typicum: Valanginian
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Original description: [McIntyre and Brideaux, 1980, p. 20]:
Diagnosis:
Shape: Pericyst - Ambitus ovoid, elongate, length/width ratio greater than 1.0; apical and antapical horns absent; dorsoventral compression. Endocyst - Ambitus as for pericyst; closely appressed throughout. Pericoels - Absent.
Phragma: Periphragm - Less than 0.5 µm thick; bearing hundreds of densely distributed processes of two main types: the most common type, very thin walled, tubular but flattened, wider basally, tapering slightly distally; distally trifurcate with stout aculei, partly open or? closed, in places distinctly connected basally by a reticulate network of very low ridges, in places apparently discrete; a second less common type, observed along what are interpreted as cingular parasutures, thin-columned, acuminate or distally slightly clavate, closed, joined basally by a system of low ridges. Length of all types, from 5-15 µm, typically 7-10 µm.
Endophragm - Indistinct, very thin, smooth.
Paratabulation: Pericyst - paratabulation indeterminate. Endocyst - Paratabulation absent. Pericingulum - On some specimens, rows of acuminate processes, seemingly connected basally, may represent pericingular parasutures. Perisulcus - Not observed.
Archeopyle: Not observed.
Variation: Orientation of many specimens uncertain; some smaller specimens may be orientated in the apical-antapical view, maximum dimensions thus representing compressed widths and depths.
Dimensions:
Maximum pericyst diameter - 30-110 µm, maximum width - 19-83 µm.
Now Prolixosphaeridium?. Originally Cleistosphaeridium, subsequently (and now) Prolixosphaeridium?.
Holotype: McIntyre and Brideaux, 1980, pl.7, fig.1-4
Locus typicus: "Grizzly Gorge", District of Mackenzie, Canada
Stratum typicum: Valanginian
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [McIntyre and Brideaux, 1980, p. 20]:
Diagnosis:
Shape: Pericyst - Ambitus ovoid, elongate, length/width ratio greater than 1.0; apical and antapical horns absent; dorsoventral compression. Endocyst - Ambitus as for pericyst; closely appressed throughout. Pericoels - Absent.
Phragma: Periphragm - Less than 0.5 µm thick; bearing hundreds of densely distributed processes of two main types: the most common type, very thin walled, tubular but flattened, wider basally, tapering slightly distally; distally trifurcate with stout aculei, partly open or? closed, in places distinctly connected basally by a reticulate network of very low ridges, in places apparently discrete; a second less common type, observed along what are interpreted as cingular parasutures, thin-columned, acuminate or distally slightly clavate, closed, joined basally by a system of low ridges. Length of all types, from 5-15 µm, typically 7-10 µm.
Endophragm - Indistinct, very thin, smooth.
Paratabulation: Pericyst - paratabulation indeterminate. Endocyst - Paratabulation absent. Pericingulum - On some specimens, rows of acuminate processes, seemingly connected basally, may represent pericingular parasutures. Perisulcus - Not observed.
Archeopyle: Not observed.
Variation: Orientation of many specimens uncertain; some smaller specimens may be orientated in the apical-antapical view, maximum dimensions thus representing compressed widths and depths.
Dimensions:
Maximum pericyst diameter - 30-110 µm, maximum width - 19-83 µm.