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Craspedodinium
From Williams et al., 2017:
[Craspedodinium, Cookson and Eisenack, 1974, p. 75; Emendation: Riding and Helby, 2001f, p.142–143
tax. jr. synonym of Ovoidinium Davey, 1970, according to Lentin and Williams, 1976. Stover and Evitt, 1978, retained Craspedodinium as a separate genus.
Type species: Craspedodinium indistinctum, Cookson and Eisenack, 1974 (pl.25, fig.7)]
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Original description: [Cookson and Eisenack, 1974]:
Description:
Shell oval in outline, flatly arched, untabulated, consisting of a not very thick-walled endophragm and a thin-walled periphragm that projects more
or less beyond the limits of the endophragm. The periphragm bears, mostly marginally, an ornamentation consisting of roundly formed meshes that are often indefinitely developed and can be lacking over large areas of the outer shell. The opening of the shell takes place by the separation of a rather large apical calotte and involves the endophragm and periphragm together.
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Modified description:
Stover and Evitt, 1978, p. 34:
Synopsis:
Cysts cavate, subspherical to ovoidal, composed of an endocyst surrounded by a loosely fitting pericyst; pericoel entire; archeopyle apical, Type tA.
Description:
Shape: Subspherical to ovoidal, apical end more
narrowly rounded than antapical end.
Wall relationships: Cavate, pericoel entire; periphragm covers endocyst loosely and is not strongly folded.
Wall features: No parasutural features. Periphragm smooth, scabrate, or locally reticulate; reticulation imperfectly developed and may be absent over relatively large areas.
Paratabulation: Indicated by archeopyle only.
Archeopyle: Apical, Type tA; opercula free.
Paracingulum: Not expressed.
Parasulcus: Not expressed.
Size: Intermediate to large.
Affinities:
Craspedodinium differs from Leberidocysta in having a somewhat tumid periphragm that contributes to the overall and fairly constant shape of the cyst; in Leberidocysta the pericyst varies in shape and is often torn or detached from the endocyst. Consequently, endocysts of Leberidocysta are frequently found without the surrounding pericyst or with only incomplete fragments of the periphragm.
[Craspedodinium, Cookson and Eisenack, 1974, p. 75; Emendation: Riding and Helby, 2001f, p.142–143
tax. jr. synonym of Ovoidinium Davey, 1970, according to Lentin and Williams, 1976. Stover and Evitt, 1978, retained Craspedodinium as a separate genus.
Type species: Craspedodinium indistinctum, Cookson and Eisenack, 1974 (pl.25, fig.7)]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Cookson and Eisenack, 1974]:
Description:
Shell oval in outline, flatly arched, untabulated, consisting of a not very thick-walled endophragm and a thin-walled periphragm that projects more
or less beyond the limits of the endophragm. The periphragm bears, mostly marginally, an ornamentation consisting of roundly formed meshes that are often indefinitely developed and can be lacking over large areas of the outer shell. The opening of the shell takes place by the separation of a rather large apical calotte and involves the endophragm and periphragm together.
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Modified description:
Stover and Evitt, 1978, p. 34:
Synopsis:
Cysts cavate, subspherical to ovoidal, composed of an endocyst surrounded by a loosely fitting pericyst; pericoel entire; archeopyle apical, Type tA.
Description:
Shape: Subspherical to ovoidal, apical end more
narrowly rounded than antapical end.
Wall relationships: Cavate, pericoel entire; periphragm covers endocyst loosely and is not strongly folded.
Wall features: No parasutural features. Periphragm smooth, scabrate, or locally reticulate; reticulation imperfectly developed and may be absent over relatively large areas.
Paratabulation: Indicated by archeopyle only.
Archeopyle: Apical, Type tA; opercula free.
Paracingulum: Not expressed.
Parasulcus: Not expressed.
Size: Intermediate to large.
Affinities:
Craspedodinium differs from Leberidocysta in having a somewhat tumid periphragm that contributes to the overall and fairly constant shape of the cyst; in Leberidocysta the pericyst varies in shape and is often torn or detached from the endocyst. Consequently, endocysts of Leberidocysta are frequently found without the surrounding pericyst or with only incomplete fragments of the periphragm.