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Araneosphaera
From Williams et al., 2017:
[Araneosphaera, Eaton, 1976, p. 239-240
Type species: Areaneosphaera araneosa, Eaton, 1976 (pl.2, fig.6; text-fig.6A)]
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Original description: [Eaton, 1976]:
Description:
Dinoflagellate cysts having a spherical or subspherical body with a smooth or finely fibroreticulate surface. Processes intratabular, fibrous, simple or branched. A variable proportion of the processes are distally united by fibrous membrane. Processes invariably present on the apical, pre- and postcingular and antapical zones. Typically each reflected plate area has one process, sometimes more than one. Cingular zone usually, but not invariably, devoid of processes. Basic reflected tabulation 4`, 6", 5-6```, 0-1p, 1````; archaeopyle precingular, formed by displacement of plate 3".
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Modified description:
Stover and Evitt, 1978, p. 142:
Synopsis:
Cysts skolochorate, gonyaulacacean; body subspherical with fibrous intratabular processes; additional accessory processes may occur on hypocyst; paracingulum typically without processes and those on hypocyst connected distally by incomplete ectophragm; archeopyle precingular, Type P.
Description:
Shape: Body subspherical.
Wall Relationships: Autophragm and incomplete ectophragm, the latter occurring only on the hypocyst.
Wall Features: No parasutural features. Processes intratabular, fibrous, normally expanded or branched distally; processes on epicyst typically free distally, those on hypocyst connected distally by ectophragm. Body smooth or fibrous between processes.
Paratabulation: Indicated by intratabular processes; gonyaulacacean, process formula 4`, 6", 0-1c, 5-6```, 0-1p, 1````; occasional accessory processes may be present.
Archeopyle: Precingular, Type P (3" only), operculum free.
Paracingulum: Indicated generally by absence of processes; occasional process may be present.
Parasulcus: Generally not indicated.
Size: Intermediate to large.
Affinities:
Araneosphaera differs from Cordosphaeridium and from Cyclapophysis in having the postcingular and antapical processes connected distally. On Cordosphaeridium all of the processes are free distally, while on Cyclapophysis the precingular and postcingular processes are joined distally instead of the hypocystal processes only, as is the case on Araneosphaera.
[Araneosphaera, Eaton, 1976, p. 239-240
Type species: Areaneosphaera araneosa, Eaton, 1976 (pl.2, fig.6; text-fig.6A)]
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Original description: [Eaton, 1976]:
Description:
Dinoflagellate cysts having a spherical or subspherical body with a smooth or finely fibroreticulate surface. Processes intratabular, fibrous, simple or branched. A variable proportion of the processes are distally united by fibrous membrane. Processes invariably present on the apical, pre- and postcingular and antapical zones. Typically each reflected plate area has one process, sometimes more than one. Cingular zone usually, but not invariably, devoid of processes. Basic reflected tabulation 4`, 6", 5-6```, 0-1p, 1````; archaeopyle precingular, formed by displacement of plate 3".
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Modified description:
Stover and Evitt, 1978, p. 142:
Synopsis:
Cysts skolochorate, gonyaulacacean; body subspherical with fibrous intratabular processes; additional accessory processes may occur on hypocyst; paracingulum typically without processes and those on hypocyst connected distally by incomplete ectophragm; archeopyle precingular, Type P.
Description:
Shape: Body subspherical.
Wall Relationships: Autophragm and incomplete ectophragm, the latter occurring only on the hypocyst.
Wall Features: No parasutural features. Processes intratabular, fibrous, normally expanded or branched distally; processes on epicyst typically free distally, those on hypocyst connected distally by ectophragm. Body smooth or fibrous between processes.
Paratabulation: Indicated by intratabular processes; gonyaulacacean, process formula 4`, 6", 0-1c, 5-6```, 0-1p, 1````; occasional accessory processes may be present.
Archeopyle: Precingular, Type P (3" only), operculum free.
Paracingulum: Indicated generally by absence of processes; occasional process may be present.
Parasulcus: Generally not indicated.
Size: Intermediate to large.
Affinities:
Araneosphaera differs from Cordosphaeridium and from Cyclapophysis in having the postcingular and antapical processes connected distally. On Cordosphaeridium all of the processes are free distally, while on Cyclapophysis the precingular and postcingular processes are joined distally instead of the hypocystal processes only, as is the case on Araneosphaera.