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Sentusidinium separatum
From Fensome et al., 2019:
Sentusidinium separatum (McIntyre and Brideaux, 1980, p.19–20, pl.6, figs.4–5,7–8) Lentin and Williams, 1981, p.254. Holotype: McIntyre and Brideaux, 1980, pl.6, figs.4–5. Originally Cleistosphaeridium, subsequently (and now) Sentusidinium. Taxonomic junior synonym: Sentusidinium cuculliforme, according to Courtinat in Fauconnier and Masure (2004, p.486) — however, Sentusidinium cuculliforme is now considered a taxonomic junior synonym of Vexillocysta colligata. Age: Valanginian.
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Original diagnosis: McIntyre and Brideaux, 1980, p. 19-20: Cleistosphaeridium separatum
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:
McIntyre and Brideaux, 1980, p. 20: Cleistosphaeridium separatum
Cleistosphaeridium separatum differs from Cleistosphaeridium huguoniotii in possessing marked accessory parasutures and narrower processes which are commonly penetabular.
Sentusidinium separatum (McIntyre and Brideaux, 1980, p.19–20, pl.6, figs.4–5,7–8) Lentin and Williams, 1981, p.254. Holotype: McIntyre and Brideaux, 1980, pl.6, figs.4–5. Originally Cleistosphaeridium, subsequently (and now) Sentusidinium. Taxonomic junior synonym: Sentusidinium cuculliforme, according to Courtinat in Fauconnier and Masure (2004, p.486) — however, Sentusidinium cuculliforme is now considered a taxonomic junior synonym of Vexillocysta colligata. Age: Valanginian.
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Original diagnosis: McIntyre and Brideaux, 1980, p. 19-20: Cleistosphaeridium separatum
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:
McIntyre and Brideaux, 1980, p. 20: Cleistosphaeridium separatum
Cleistosphaeridium separatum differs from Cleistosphaeridium huguoniotii in possessing marked accessory parasutures and narrower processes which are commonly penetabular.