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Hexagonifera
From Williams et al., 2017:
[Hexagonifera, Cookson and Eisenack, 1961a, p. 73-74; Emendations: Cookson and Eisenack, 1962b, p. 496; Stover and Evitt, 1978, p. 107–108.
Type species: Hexagonifera glabra, Cookson and Eisenack, 1961a (pl.12, fig.11)]
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Original description: [Cookson and Eisenack, 1961]:
Description:
Shell oval, wall of variable thickness, smooth or ornamented. Pylomle formed by the removal of a 6-sided lid at one pole.
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Emended description:
Cookson and Eisenack, 1962:
Description:
Shell oval, either without or partially or completely enclosed in a thin, transparent, detachable membrane; wall of variable thickness, smooth or variously sculptured. Pylome formed by the removal of a six-sided portion of the shell at one end.
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Stover and Evitt, 1978:
Synopsis:
Cysts proximate, subspherical to lenticular, without horns; autophragm smooth or ornamented with features of low relief; paratabulation indicated generally by archeopyle only, other indications faint or lacking; archeopyle intercalary, Type l; archeopyle index >0.5.
Description:
Shape: Subspherical to lenticular.
Wall relationships: Autophragm only.
Wall features: No parasutural features. Autophragm smooth or ornamented with features of low relief.
Paratabulation: Indicated generally by archeopyle only; other indications indistinct or absent.
Archeopyle: Intercalary, Type I (2a only); archeopyle index >0.5.
Paracingulum: Not indicated, or indicated by faint transverse markings.
Parasulcus: Not indicated.
Size: Intermediate.
Affinites:
Hexagonifera differs from Pyxidiella in being subspherical to lenticular rather than elongate ellipsoidal. Retention of both genera based essentially on a difference in shape hardly seems justified.
[Hexagonifera, Cookson and Eisenack, 1961a, p. 73-74; Emendations: Cookson and Eisenack, 1962b, p. 496; Stover and Evitt, 1978, p. 107–108.
Type species: Hexagonifera glabra, Cookson and Eisenack, 1961a (pl.12, fig.11)]
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Original description: [Cookson and Eisenack, 1961]:
Description:
Shell oval, wall of variable thickness, smooth or ornamented. Pylomle formed by the removal of a 6-sided lid at one pole.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Emended description:
Cookson and Eisenack, 1962:
Description:
Shell oval, either without or partially or completely enclosed in a thin, transparent, detachable membrane; wall of variable thickness, smooth or variously sculptured. Pylome formed by the removal of a six-sided portion of the shell at one end.
-------------------------------------
Stover and Evitt, 1978:
Synopsis:
Cysts proximate, subspherical to lenticular, without horns; autophragm smooth or ornamented with features of low relief; paratabulation indicated generally by archeopyle only, other indications faint or lacking; archeopyle intercalary, Type l; archeopyle index >0.5.
Description:
Shape: Subspherical to lenticular.
Wall relationships: Autophragm only.
Wall features: No parasutural features. Autophragm smooth or ornamented with features of low relief.
Paratabulation: Indicated generally by archeopyle only; other indications indistinct or absent.
Archeopyle: Intercalary, Type I (2a only); archeopyle index >0.5.
Paracingulum: Not indicated, or indicated by faint transverse markings.
Parasulcus: Not indicated.
Size: Intermediate.
Affinites:
Hexagonifera differs from Pyxidiella in being subspherical to lenticular rather than elongate ellipsoidal. Retention of both genera based essentially on a difference in shape hardly seems justified.