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Hystrichodinium dasum
From Fensome et al., 2019:
Hystrichodinium? dasum Davey, 1969a, p.175–176, pl.10, figs.8–9. Holotype: Davey, 1969a, pl.10, fig.8. Originally Hystrichodinium, subsequently (and now) Hystrichodinium?. Questionable assignment: Stover and Evitt (1978, p.162). Principle V of the ICN states that "... names of taxonomic groups are treated as Latin regardless of their origin." Thus, the epithet "dasys" should be Latinized to "dasus", with the neuter form being "dasum". Age: Cenomanian.
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Locus typicus: Escalles, France
Original diagnosis: Davey, 1969, p. 176
Shell subspherical, thin-walled, smooth or slightly granular. Tabulation very faintly marked; cingulum, and more rarely, precingular and postcingular plate boundaries visible. Processes numerous, short, fine and flexuous, aligned along plate boundaries, also intratabular. Archaeopyle not observed.
Dimensions: diameter of central body 42 (53) 70 µm, maximum length of processes 7 (10.6) 14 µm.
Original description: Davey, 1969, p. 176
The shell, being thin-walled, is always found deformed. Only two specimens possess a faint tabulation. This is best seen in the holotype which has a clear but lightly defined cingulum and two or three precingular and postcingular plate boundaries visible. The numerous processes are hair-like, approximately 0.2 µm wide for most of their length, probably hollow and terminate with a point. The most characteristic feature of the proccsses is their extreme flexibility.
Affinities:
Davey, 1969, p. 176: The characteristic processes and the presence of a tabulation differentiate H. dasum very easily from all previously described microplankton species.
Hystrichodinium? dasum Davey, 1969a, p.175–176, pl.10, figs.8–9. Holotype: Davey, 1969a, pl.10, fig.8. Originally Hystrichodinium, subsequently (and now) Hystrichodinium?. Questionable assignment: Stover and Evitt (1978, p.162). Principle V of the ICN states that "... names of taxonomic groups are treated as Latin regardless of their origin." Thus, the epithet "dasys" should be Latinized to "dasus", with the neuter form being "dasum". Age: Cenomanian.
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Locus typicus: Escalles, France
Original diagnosis: Davey, 1969, p. 176
Shell subspherical, thin-walled, smooth or slightly granular. Tabulation very faintly marked; cingulum, and more rarely, precingular and postcingular plate boundaries visible. Processes numerous, short, fine and flexuous, aligned along plate boundaries, also intratabular. Archaeopyle not observed.
Dimensions: diameter of central body 42 (53) 70 µm, maximum length of processes 7 (10.6) 14 µm.
Original description: Davey, 1969, p. 176
The shell, being thin-walled, is always found deformed. Only two specimens possess a faint tabulation. This is best seen in the holotype which has a clear but lightly defined cingulum and two or three precingular and postcingular plate boundaries visible. The numerous processes are hair-like, approximately 0.2 µm wide for most of their length, probably hollow and terminate with a point. The most characteristic feature of the proccsses is their extreme flexibility.
Affinities:
Davey, 1969, p. 176: The characteristic processes and the presence of a tabulation differentiate H. dasum very easily from all previously described microplankton species.