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Eurydinium
From Williams et al., 2017:
[Eurydinium, Stover and Evitt, 1978, p. 104-105
Type species: as Deflandrea ingramii, Cookson and Eisenack, 1970a (pl.12, fig.9)] ; Eurydinium ingramii, Stover and Evitt, 1978
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Original description: [Stover and Evitt, 1978]:
Synopsis:
Cysts proximate, cavate, lenticular to compressed ellipsoidal, typically without horns or with an apical horn; pericyst smooth or variously and uniformly ornamented; endocyst outline elliptical, length greater than width; paratabulation indicated by archeopyle only, or by paracingulum and archeopyle; latter intercalary, Type I or la; archeopyle index <0.5.
Description:
Shape: Lenticular to compressed ellipsoidal; pericyst typically without horns or with an apical horn.
Wall relationships: Cysts bicavate or circumcavate; endocyst outline elliptical, length greater than width.
Wall features: No parasutural features. Periphragm smooth or ornamented uniformly with features of low relief.
Paratabulation: Indicated by archeopyle only, or by archeopyle and paracingulum.
Archeopyle: Intercalary, Type I or la (2a only); archeopyle index <0.5, generally about 0.3; operculum free or attached.
Paracingulum: Not indicated, or expressed by low transverse parallel folds, by alignment of ornamentation, and/or by local concavities along the lateral margins.
Parasulcus: Generally not indicated.
Size: Intermediate to large.
Affinities:
The basic difference between Eurydinium and Isabelidinium is that in the former the length of the endocyst is greater than its width, whereas in the latter, its length is equal to or less than its width.
[Eurydinium, Stover and Evitt, 1978, p. 104-105
Type species: as Deflandrea ingramii, Cookson and Eisenack, 1970a (pl.12, fig.9)] ; Eurydinium ingramii, Stover and Evitt, 1978
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Stover and Evitt, 1978]:
Synopsis:
Cysts proximate, cavate, lenticular to compressed ellipsoidal, typically without horns or with an apical horn; pericyst smooth or variously and uniformly ornamented; endocyst outline elliptical, length greater than width; paratabulation indicated by archeopyle only, or by paracingulum and archeopyle; latter intercalary, Type I or la; archeopyle index <0.5.
Description:
Shape: Lenticular to compressed ellipsoidal; pericyst typically without horns or with an apical horn.
Wall relationships: Cysts bicavate or circumcavate; endocyst outline elliptical, length greater than width.
Wall features: No parasutural features. Periphragm smooth or ornamented uniformly with features of low relief.
Paratabulation: Indicated by archeopyle only, or by archeopyle and paracingulum.
Archeopyle: Intercalary, Type I or la (2a only); archeopyle index <0.5, generally about 0.3; operculum free or attached.
Paracingulum: Not indicated, or expressed by low transverse parallel folds, by alignment of ornamentation, and/or by local concavities along the lateral margins.
Parasulcus: Generally not indicated.
Size: Intermediate to large.
Affinities:
The basic difference between Eurydinium and Isabelidinium is that in the former the length of the endocyst is greater than its width, whereas in the latter, its length is equal to or less than its width.