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Ripea
From Williams et al., 2017:
[Ripea, Batten, 1985, p. 431; Emendation: Batten and Lister, 1988, p.354
Type species: Ripea sussexensis, Batten, 1985 (text-figs.3B,5A)]
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Original description: [Batten, 1985]:
Description:
Small, thin walled peridiniinean cyst of essentially triangular shape with rounded angles, two of which are weakly developed antapical lobes. Wall two layered; periphragm closely adpressed to endophragm adjacent to archeopyle but more loosely enveloping towards the antapex. Paracingulum usually absent but very occasionally faintly evident.
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Modified description:
Stover and Williams, 1987, p. 193, 431:
Synopsis:
Cysts proximate, outline roundly triangular with two poorly-developed antapical lobes; endophragm and periphragm appressed adjacent to the archeopyle, separated posteriorly, cavation indistinct; paratabulation indicated generally by 3I archeopyle only.
Description:
Shape: Outline roundly triangular, but may be severely modified by folding; poorly-developed antapical lobes present.
Wall relationships: Endophragm and periphragm appressed apically and adjacent to archeopyle; indistinctly separated posterior to archeopyle.
Wall features: No parasutural features or projections; both wall layers thin, usually complexly folded.
Archeopyle: Type 3I; additional information not given.
Paratabulation: Indicated mainly by archeopyle only.
Paracingulum. Usually not indicated.
Parasulcus: Not indicated.
Size: Small, overall size about 30 to 35 µm.
Affinities:
Ripea differs from Saeptodinium Harris 1974, in having an intercalary rather than a combination archeopyle, and from Morkallacysta Harris 1974 - which has an intercalary archeopyle - in lacking prominent apical and antapical horns.
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Emended description:
Batten and Lister, 1988:
Diagnosis:
Small, thin-walled peridiniacean cyst of essentially triangular shape with rounded angles, two of which are weakly developed antapical lobes. Wall two-layered; periphragm closely adpressed to endophragm adjacent to archeopyle but more loosely enveloping towards the antapex. Paracingulum usually absent but occasionally faintly evident in part. Paratabulation expressed by archeopyle, type tI or tI +(tA), and occasional accessory sutures between precingular paraplates.
[Ripea, Batten, 1985, p. 431; Emendation: Batten and Lister, 1988, p.354
Type species: Ripea sussexensis, Batten, 1985 (text-figs.3B,5A)]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Batten, 1985]:
Description:
Small, thin walled peridiniinean cyst of essentially triangular shape with rounded angles, two of which are weakly developed antapical lobes. Wall two layered; periphragm closely adpressed to endophragm adjacent to archeopyle but more loosely enveloping towards the antapex. Paracingulum usually absent but very occasionally faintly evident.
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Modified description:
Stover and Williams, 1987, p. 193, 431:
Synopsis:
Cysts proximate, outline roundly triangular with two poorly-developed antapical lobes; endophragm and periphragm appressed adjacent to the archeopyle, separated posteriorly, cavation indistinct; paratabulation indicated generally by 3I archeopyle only.
Description:
Shape: Outline roundly triangular, but may be severely modified by folding; poorly-developed antapical lobes present.
Wall relationships: Endophragm and periphragm appressed apically and adjacent to archeopyle; indistinctly separated posterior to archeopyle.
Wall features: No parasutural features or projections; both wall layers thin, usually complexly folded.
Archeopyle: Type 3I; additional information not given.
Paratabulation: Indicated mainly by archeopyle only.
Paracingulum. Usually not indicated.
Parasulcus: Not indicated.
Size: Small, overall size about 30 to 35 µm.
Affinities:
Ripea differs from Saeptodinium Harris 1974, in having an intercalary rather than a combination archeopyle, and from Morkallacysta Harris 1974 - which has an intercalary archeopyle - in lacking prominent apical and antapical horns.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Emended description:
Batten and Lister, 1988:
Diagnosis:
Small, thin-walled peridiniacean cyst of essentially triangular shape with rounded angles, two of which are weakly developed antapical lobes. Wall two-layered; periphragm closely adpressed to endophragm adjacent to archeopyle but more loosely enveloping towards the antapex. Paracingulum usually absent but occasionally faintly evident in part. Paratabulation expressed by archeopyle, type tI or tI +(tA), and occasional accessory sutures between precingular paraplates.