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Cleistosphaeridium separatum

Cleistosphaeridium separatum, McIntyre and Brideaux, 1980

Holotype: McIntyre and Brideaux, 1980, pl.6, figs.4-5
Locus typicus: District of Mackenzie, Canada
Stratum typicum: Valanginian

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Original description: [McIntyre and Brideaux, 1980, p. 19-20]:

Diagnosis:
Shape: Pericyst - Complete pericyst not observed, the remaining portion nearly hemispherical; antapex rounded. Dorsoventral compression. Endocyst - Commonly obscure, closely appressed to the pericyst. Pericoels - Not observed.
Phragma: Periphragm - About 0.5 µm thick; surface sculpture of fine granulate to echinate elements less than 0.5 µm high; processes arising from periphragm closed, distally bifid to finely branched, 2-8 µm long (typically 4-7 µm) and about 1 µm wide; in places on some specimens, processes concentrated in penetabular position on paraplates and reduced in density or absent in the interior of paraplates; 15-20 processes per paraplate. Endophragm - Commonly obscure, less than 0.5 µm thick; presumably smooth.
Paratabulation: Pericyst - Marked development of accessory parasutures in the vicinity of the archeopyle and penetabular concentration of processes denote an epiparatabulation of 4", 0a, 6" and ?c; less pronounced penetabular concentration of processes denotes a hypoparatabulation of ? (5"""-6""", 1"""", ?p). Endocyst - Paratabulation not observed. Pericingulum - Not observed. Perisulcus - Present on one specimen, position denoted by distinct sulcal notch; parasulcal processes discrete and apparently parasutural, denoting an anterior sulcal paraplate and one or more sulcal paraplates.
Archeopyle: Apical, Type A(1"-4"). Operculum free and? simple.

Dimensions:
Pericyst length - 23-42 µm (archeopyle developed); width - 30-52 µm.

Affinities:
Cleistosphaeridium separatum differs from Cleistosphaeridium huguoniotii in possessing marked accessory parasutures and narrower processes which are commonly penetabular.
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