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Fromea
From Williams et al., 2017:
[Fromea, Cookson and Eisenack, 1958, p. 55; Emendation: Yun, 1981, p. 55
Acritarch genus, according to Duxbury, 1980, and Fensome et al., 1990
Type species: Fromea amphora, Cookson and Eisenack, 1958 (pl.5, fig.10)]
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Original description: [Cookson and Eisenack, 1958]: (Translation Yun, 1981: LPP):
Description:
Shell elongate, smooth with an equatorial girdle and a wide aperture at one end.
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Modified description:
Stover and Evitt, 1978, p. 47:
Synopsis:
Cysts ellipsoidal, smooth or faintly ornamented; archeopyle at apex, type uncertain; indications of paracingulum may be present.
Description:
Shape: Ellipsoidal.
Wall relationships: Autophragm only.
Wall features: No parasutural features. Autophragm smooth or faintly ornamented.
Paratabulation: Not indicated.
Archeopyle: At apex, type uncertain; suture slightly concave in lateral view; operculum free.
Paracingulum: Indicated at about midlength by a transverse line or by parallel transverse lines. Paracingulum not always indicated.
Parasulcus: Not indicated.
Size: Small to intermediate.
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Emended description:
Yun, 1981:
Diagnosis:
The single layered oval cyst is smooth or sculptured. The apical archaeopyle with round edge shows a small diameter. The ratio archaeopyle / width of cyst is 0.3 - 0.9. The shortest distance between paracingulum and archaeopyle (length of precingulare paraplates) is always more than half of the cyst width. Usually are the paracingulum, rarely the parasulcus and the paratabulation indicated by dents or folding.
Affinities:
Fromea differs from Palaeostomocystis in being smooth rather than reticulate.
[Fromea, Cookson and Eisenack, 1958, p. 55; Emendation: Yun, 1981, p. 55
Acritarch genus, according to Duxbury, 1980, and Fensome et al., 1990
Type species: Fromea amphora, Cookson and Eisenack, 1958 (pl.5, fig.10)]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Cookson and Eisenack, 1958]: (Translation Yun, 1981: LPP):
Description:
Shell elongate, smooth with an equatorial girdle and a wide aperture at one end.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Modified description:
Stover and Evitt, 1978, p. 47:
Synopsis:
Cysts ellipsoidal, smooth or faintly ornamented; archeopyle at apex, type uncertain; indications of paracingulum may be present.
Description:
Shape: Ellipsoidal.
Wall relationships: Autophragm only.
Wall features: No parasutural features. Autophragm smooth or faintly ornamented.
Paratabulation: Not indicated.
Archeopyle: At apex, type uncertain; suture slightly concave in lateral view; operculum free.
Paracingulum: Indicated at about midlength by a transverse line or by parallel transverse lines. Paracingulum not always indicated.
Parasulcus: Not indicated.
Size: Small to intermediate.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Emended description:
Yun, 1981:
Diagnosis:
The single layered oval cyst is smooth or sculptured. The apical archaeopyle with round edge shows a small diameter. The ratio archaeopyle / width of cyst is 0.3 - 0.9. The shortest distance between paracingulum and archaeopyle (length of precingulare paraplates) is always more than half of the cyst width. Usually are the paracingulum, rarely the parasulcus and the paratabulation indicated by dents or folding.
Affinities:
Fromea differs from Palaeostomocystis in being smooth rather than reticulate.