Back
Cleistosphaeridium oligacanthum
Cleistosphaeridium oligocanthum, (W.Wetzel, 1952), Davey et al. 1969
Originally Hystrichosphaeridium, subsequently Baltisphaeridium, thirdly Cleistosphaeridium?, fourthly Laticavodinium, fifthly Cleistosphaeridium?, sixthly (and now) Impletosphaeridium.
At the time of the transfer, Davey et al., 1969, questionably included this species in Cleistosphaeridium.
Stover and Evitt, 1978, considered this to be a provisionally accepted species of Cleistosphaeridium.
This combination was not validly published in Davey et al., 1966, since these authors did not fully reference the basionyrn.
Davey et al., 1966, also questionably included this species in Cleistosphaeridium.
Holotype: W. Wetzel, 1952, pl.A, fig.8; Sarjeant, 1984, pl.2, figs.4-5; text-fig.2
Locus typicus: Kiel district, Germany
Stratum typicum: Danian
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
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.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
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.
Originally Hystrichosphaeridium, subsequently Baltisphaeridium, thirdly Cleistosphaeridium?, fourthly Laticavodinium, fifthly Cleistosphaeridium?, sixthly (and now) Impletosphaeridium.
At the time of the transfer, Davey et al., 1969, questionably included this species in Cleistosphaeridium.
Stover and Evitt, 1978, considered this to be a provisionally accepted species of Cleistosphaeridium.
This combination was not validly published in Davey et al., 1966, since these authors did not fully reference the basionyrn.
Davey et al., 1966, also questionably included this species in Cleistosphaeridium.
Holotype: W. Wetzel, 1952, pl.A, fig.8; Sarjeant, 1984, pl.2, figs.4-5; text-fig.2
Locus typicus: Kiel district, Germany
Stratum typicum: Danian
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
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.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
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.