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Conosphaeridium
From Williams et al., 2017:
[Conosphaeridium, Cookson and Eisenack, 1969, p. 5;
tax. jr. synonym of Litosphaeridium Davey and Williams, 1966, according to Sarjeant, 1969. Lentin and Williams, 1973, retained Conosphaeridium as a separate genus.
Type species: originally as Hystrichosphaeridium striatoconum, Deflandre and Cookson, 1955 (text-fig.36)] ; Conosphaeridium striatoconus, Cookson and Eisenack, 1969
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Original description: Cookson and Eisenack, 1969
Shell circular in outline with a single-layered wall of varying thickness and about 20 regularly distributed conical to cylindrical, striated appendages; archeopyle circular to polygonal.
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Modified description:
Stover and Evitt, 1978, p. 145-146:
Synopsis:
Cysts skolochorate, body subspherical, bearing approximately 20 to 25 conical to elongate, intratabular, nonfibrous processes whose tips are
normally narrower than their bases; paratabulation indicated by processes; archeopyle precingular, Type P.
Description:
Shape: Body subspherical.
Wall relationships: Endophragm and periphragm appressed between processes.
Wall features: No parasutural features. Intratabular processes nonfibrous, striated, conical to elongate; bases wider than tips and closed distally; periphragm between processes smooth or faintly ornamented.
Paratabulation: Indicated by intratabular processes; gonyaulacacean, exact formula unknown, most likely 3-4` , 6", 6c, 5-6```, 1p, 1````.
Archeopyle: Precingular, Type P (3`` only); operculum free.
Paracingulum: Position indicated by six intratabular processes.
Parasulcus: Mode of expression unknown, probably not clearly indicated.
Size: Intermediate to large.
Affinities:
Conosphaeridium differs from Litosphaeridium in having a precingular archeopyle; from Cordosphaeridium in having nonfibrous processes; and from Kleithriasphaeridium in having processes with narrow tips that are closed distally. In Kleithriasphaeridium the processes are open and tend to expand distally. Conosphaeridium differs from Aireiana in having paracingular processes, which are not present in the latter genus.
[Conosphaeridium, Cookson and Eisenack, 1969, p. 5;
tax. jr. synonym of Litosphaeridium Davey and Williams, 1966, according to Sarjeant, 1969. Lentin and Williams, 1973, retained Conosphaeridium as a separate genus.
Type species: originally as Hystrichosphaeridium striatoconum, Deflandre and Cookson, 1955 (text-fig.36)] ; Conosphaeridium striatoconus, Cookson and Eisenack, 1969
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: Cookson and Eisenack, 1969
Shell circular in outline with a single-layered wall of varying thickness and about 20 regularly distributed conical to cylindrical, striated appendages; archeopyle circular to polygonal.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Modified description:
Stover and Evitt, 1978, p. 145-146:
Synopsis:
Cysts skolochorate, body subspherical, bearing approximately 20 to 25 conical to elongate, intratabular, nonfibrous processes whose tips are
normally narrower than their bases; paratabulation indicated by processes; archeopyle precingular, Type P.
Description:
Shape: Body subspherical.
Wall relationships: Endophragm and periphragm appressed between processes.
Wall features: No parasutural features. Intratabular processes nonfibrous, striated, conical to elongate; bases wider than tips and closed distally; periphragm between processes smooth or faintly ornamented.
Paratabulation: Indicated by intratabular processes; gonyaulacacean, exact formula unknown, most likely 3-4` , 6", 6c, 5-6```, 1p, 1````.
Archeopyle: Precingular, Type P (3`` only); operculum free.
Paracingulum: Position indicated by six intratabular processes.
Parasulcus: Mode of expression unknown, probably not clearly indicated.
Size: Intermediate to large.
Affinities:
Conosphaeridium differs from Litosphaeridium in having a precingular archeopyle; from Cordosphaeridium in having nonfibrous processes; and from Kleithriasphaeridium in having processes with narrow tips that are closed distally. In Kleithriasphaeridium the processes are open and tend to expand distally. Conosphaeridium differs from Aireiana in having paracingular processes, which are not present in the latter genus.