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Galeacysta
From Williams et al., 2017:
[Galeacysta, Corradini and Biffi, 1988, p. 225
Type species: Galeacysta etrusca, Corradini and Biffi, 1988 (pl.1, figs.4–5)]
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Original description: [Corradini and Biffi, 1988]: (Translation: Fensome et al., 1991, p. 237 (diagnosis) and LPP):
Diagnosis:
Cyst camocavate. Endocyst ellipsoidal, pericyst ellipsoidal to subpolygonal. Endophragm and periphragm appressed dorsally, but distinctly separated in the ventral area. Endophragm smooth, periphragm smooth to finely granular, irregularly perforate or fenestrate.
The gonyaulacoid paratabulation is indicated by parasutural lines and intratabular openings of the periphragm: the formula is 4`, 6``, 6c, 6```, 1p, 1ps, 1````.
The periphragm is absent over most of the sulcal area.
The archeopyle is precingular, type P (3``). The operculum is free.
Affinities:
Galeacysta differs from Lophocysta Manum, 1979, in the presence of parasutural ridges on the dorsal and ventral side of the periphragm, delineating a gonyaulacoid paratabulation, the absence of the periphragm in the sulcal area, the absence of "processes" in gonal position in the dorsal area, and the development of large intratabular claustra in the periphragm.
Tahlassiphora Eisenack and Gocht, 1960; emend. Gocht, 1968, has a direct affinity with Galeacysta, especially the species which have traces of paratabulation on the periphragm, like T. delicata Williams and Downie, 1966; emend. Eaton, 1976. Galeacysta mainly differs from them in the very pronounced paratabulation on the entire periphragm, the constant absence of the periphragm in the sulcal area, and the presence of large intratabular claustra corresponding to the paraplates.
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Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Galeacysta Corradini and Biffi, 1988. Camocavate, according to Corradini and Biffi (1988, p.225), with endocyst ellipsoidal and pericyst ellipsoidal to subpolygonal. Endophragm and periphragm appressed dorsally, but separated in ventral area. Periphragm may be fenestrate or perforate. Periphragm absent from most of sulcal area. Tabulation 4`, 6", 6c, 6"', 1p, 1ps, 1"''. Archeopyle precingular, type P (3"), with free operculum.
[Galeacysta, Corradini and Biffi, 1988, p. 225
Type species: Galeacysta etrusca, Corradini and Biffi, 1988 (pl.1, figs.4–5)]
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Original description: [Corradini and Biffi, 1988]: (Translation: Fensome et al., 1991, p. 237 (diagnosis) and LPP):
Diagnosis:
Cyst camocavate. Endocyst ellipsoidal, pericyst ellipsoidal to subpolygonal. Endophragm and periphragm appressed dorsally, but distinctly separated in the ventral area. Endophragm smooth, periphragm smooth to finely granular, irregularly perforate or fenestrate.
The gonyaulacoid paratabulation is indicated by parasutural lines and intratabular openings of the periphragm: the formula is 4`, 6``, 6c, 6```, 1p, 1ps, 1````.
The periphragm is absent over most of the sulcal area.
The archeopyle is precingular, type P (3``). The operculum is free.
Affinities:
Galeacysta differs from Lophocysta Manum, 1979, in the presence of parasutural ridges on the dorsal and ventral side of the periphragm, delineating a gonyaulacoid paratabulation, the absence of the periphragm in the sulcal area, the absence of "processes" in gonal position in the dorsal area, and the development of large intratabular claustra in the periphragm.
Tahlassiphora Eisenack and Gocht, 1960; emend. Gocht, 1968, has a direct affinity with Galeacysta, especially the species which have traces of paratabulation on the periphragm, like T. delicata Williams and Downie, 1966; emend. Eaton, 1976. Galeacysta mainly differs from them in the very pronounced paratabulation on the entire periphragm, the constant absence of the periphragm in the sulcal area, and the presence of large intratabular claustra corresponding to the paraplates.
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Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Galeacysta Corradini and Biffi, 1988. Camocavate, according to Corradini and Biffi (1988, p.225), with endocyst ellipsoidal and pericyst ellipsoidal to subpolygonal. Endophragm and periphragm appressed dorsally, but separated in ventral area. Periphragm may be fenestrate or perforate. Periphragm absent from most of sulcal area. Tabulation 4`, 6", 6c, 6"', 1p, 1ps, 1"''. Archeopyle precingular, type P (3"), with free operculum.