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Cleistosphaeridium oligacanthum
From Fensome et al., 2019:
Cleistosphaeridium oligocanthum (Wetzel, 1952, p.402–405, pl.A, figs.4,7–8,11a–b; text-figs.21–25) Davey et al., 1969, p.16. Emendation: Wilson and Sarjeant in Sarjeant, 1984c, p.128, as Laticavodinium oligacanthum. Holotype: Wetzel,
1952, pl.A, fig.8; Sarjeant, 1984c, pl.2, figs.4–5; text-fig.2; Fensome et al., 1995, figs.1–5 — p.1625; Dietz et al.,
1999, text-fig.6g. NOW Impletosphaeridium. Originally Hystrichosphaeridium, subsequently Baltisphaeridium
(Appendix A), thirdly Cleistosphaeridium?, fourthly Laticavodinium, fifthly (and now) Impletosphaeridium?.
Questionable assignment: Davey et al. (1969, p.16). This combination was not validly published in Davey et al.
(1966, p.170), since these authors did not fully reference the basionym. Age: Danian.
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Original diagnosis as Hystrichosphaeridium oligocanthum: [W. Wetzel, 1952, p. 403]: (Translation: Sarjeant, 1984):
Diagnosis:
Principal characteristics are relatively stately dimensions, thick-walled capsule and processes which produce only insignificant, narrow tubes distally [and] which, as a result of their "softness" [lack of rigidity] may be bent into curves. The number of processes may vary considerably, but is perhaps in most cases to be denoted as moderate. Curvature of the processes is common, but not regular.
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Emended diagnosis as Laticavodinium oligocanthum:
Wilson and Sarjeant, 1984, p. 128:
Diagnosis:
Cyst proximochorate to proximate, spiniferate. Central body broadly ovoidal.
Paratabulation marked by low ridges along paraplate junctions (sometimes only feebly developed) and by gonal and intergonal processes; paratabulation 4", 0a, 6", ?6c, 5""", 1p, 1"""".
Processes variable in length and thickness according to their position on the cyst. Apical processes thin and relatively short, bifid or trifid, with brief, typically symmetrical branches. Other processes longer, bifid or trifid, with brief branches of equal or unequal length; these branches may be, in a few instances, briefly bifurcate. The process at the junction of paraplates 3""" and 4""" with the cingulum is markedly larger and thicker than the others and may be open distally.
Surface of phragma typically ornamented with granules, sometimes showing in places a small-scale reticulation.
Archaeopyle precingular, formed by the loss of paraplates 2" and 3".
Dimensions:
Holotype (in polar view); shortest equatorial diameter 71 µm, longest 74 µm, length of processes c. 20-28 µm.
Cleistosphaeridium oligocanthum (Wetzel, 1952, p.402–405, pl.A, figs.4,7–8,11a–b; text-figs.21–25) Davey et al., 1969, p.16. Emendation: Wilson and Sarjeant in Sarjeant, 1984c, p.128, as Laticavodinium oligacanthum. Holotype: Wetzel,
1952, pl.A, fig.8; Sarjeant, 1984c, pl.2, figs.4–5; text-fig.2; Fensome et al., 1995, figs.1–5 — p.1625; Dietz et al.,
1999, text-fig.6g. NOW Impletosphaeridium. Originally Hystrichosphaeridium, subsequently Baltisphaeridium
(Appendix A), thirdly Cleistosphaeridium?, fourthly Laticavodinium, fifthly (and now) Impletosphaeridium?.
Questionable assignment: Davey et al. (1969, p.16). This combination was not validly published in Davey et al.
(1966, p.170), since these authors did not fully reference the basionym. Age: Danian.
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Original diagnosis as Hystrichosphaeridium oligocanthum: [W. Wetzel, 1952, p. 403]: (Translation: Sarjeant, 1984):
Diagnosis:
Principal characteristics are relatively stately dimensions, thick-walled capsule and processes which produce only insignificant, narrow tubes distally [and] which, as a result of their "softness" [lack of rigidity] may be bent into curves. The number of processes may vary considerably, but is perhaps in most cases to be denoted as moderate. Curvature of the processes is common, but not regular.
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Emended diagnosis as Laticavodinium oligocanthum:
Wilson and Sarjeant, 1984, p. 128:
Diagnosis:
Cyst proximochorate to proximate, spiniferate. Central body broadly ovoidal.
Paratabulation marked by low ridges along paraplate junctions (sometimes only feebly developed) and by gonal and intergonal processes; paratabulation 4", 0a, 6", ?6c, 5""", 1p, 1"""".
Processes variable in length and thickness according to their position on the cyst. Apical processes thin and relatively short, bifid or trifid, with brief, typically symmetrical branches. Other processes longer, bifid or trifid, with brief branches of equal or unequal length; these branches may be, in a few instances, briefly bifurcate. The process at the junction of paraplates 3""" and 4""" with the cingulum is markedly larger and thicker than the others and may be open distally.
Surface of phragma typically ornamented with granules, sometimes showing in places a small-scale reticulation.
Archaeopyle precingular, formed by the loss of paraplates 2" and 3".
Dimensions:
Holotype (in polar view); shortest equatorial diameter 71 µm, longest 74 µm, length of processes c. 20-28 µm.