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Fibradinium
From Fensome et al., 2019:
Fibradinium, Morgenroth, 1968, p.537–538.
Taxonomic senior synonym: Phanerodinium, according to Below (1987b, p.36) -- however, Lentin and Williams (1993, p.221) retained Fibradinium.
Type: Morgenroth, 1968, pl.42, fig.4, as Fibradinium annetorpense.
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Original description: [Morgenroth, 1968]: (Translation: Stover and Evitt, 1978, p.47):
Description:
Theca without processes, weakly ellipsoidal. Thecal wall composed of two layers of which the inner one is a smooth membrane, the outer one fibrous. Tabulation formula: ?7`, 6", 6, 6```, 1p, 1````. Cingulum equatorial, circular to weakly spiral to the left. Sulcus undifferentiated.
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Modified description:
Stover and Evitt, 1978, p. 47:
Synopsis:
Cysts proximate, subspherical; autophragm fibrous; gonyaulacacean, paratabulation indicated by parasutural ridges, formula: ?7`, 6", 6c, 6```, 1p, 1````, 1-3s; archeopyle at apex, type uncertain.
Description:
Shape: Subspherical.
Wall relationships: Autophragm only.
Wall features: Parasutural ridges low, with granular appearance. Autophragm fibrous.
Paratabulation: Indicated by parasutural ridges; gonyaulacacean, formula: ?7`, 6", 6c, 6```,1p, 1````, 1-3s; number of paraplates at apex not known with certainty, may include intercalaries.
Archaeopyle: At apex, type uncertain; exact outline of archaeopyle and operculum unknown.
Paracingulum: Indicated by six transversely elongate, rectangular paraplates.
Parasulcus: Outlined by parasutural ridges; longitudinally elongate, wide antapically, narrow and subdivided apically.
Size: Small.
Affinities:
Fibradinium differs from Microdinium in having a fibrous rather than a smooth or weakly ornamented autophragm.
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Emended description Vieira et al., 2025:
Emended diagnosis: Cysts subspherical; gonyaulacacean, paratabulation indicated by parasutural ridges, formula 5′, 5a, 7″, 6c, 7″’, 1p, 1″“.
Emended description: Cysts are small, subspherical, with a smaller epicyst than the hypocyst. The periphragm displays ridges and shallow penitabular indentations“. SEM analysis shows that the latter features form complete rings around some paraplates. The tabulation, determined through SEM, follows a pattern of 5’, 5a, 7”, 6c, 7″’, 1p, 1″“. The archeopyle is apical-intercalary (tAtI)a, with an operculum typically attached to the anterior sulcal paraplate.
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Fibradinium Morgenroth, 1968. Theca without processes, weakly ellipsoidal. Thecal wall composed of two layers of which the inner one is a smooth membrane, the outer one fibrous. Tabulation formula: ?7`, 6", 6c. 6"', 1p, 1"''. Cingulum equatorial, circular to weakly spiral to the left. Sulcus undifferentiated.
Fibradinium, Morgenroth, 1968, p.537–538.
Taxonomic senior synonym: Phanerodinium, according to Below (1987b, p.36) -- however, Lentin and Williams (1993, p.221) retained Fibradinium.
Type: Morgenroth, 1968, pl.42, fig.4, as Fibradinium annetorpense.
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Morgenroth, 1968]: (Translation: Stover and Evitt, 1978, p.47):
Description:
Theca without processes, weakly ellipsoidal. Thecal wall composed of two layers of which the inner one is a smooth membrane, the outer one fibrous. Tabulation formula: ?7`, 6", 6, 6```, 1p, 1````. Cingulum equatorial, circular to weakly spiral to the left. Sulcus undifferentiated.
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Modified description:
Stover and Evitt, 1978, p. 47:
Synopsis:
Cysts proximate, subspherical; autophragm fibrous; gonyaulacacean, paratabulation indicated by parasutural ridges, formula: ?7`, 6", 6c, 6```, 1p, 1````, 1-3s; archeopyle at apex, type uncertain.
Description:
Shape: Subspherical.
Wall relationships: Autophragm only.
Wall features: Parasutural ridges low, with granular appearance. Autophragm fibrous.
Paratabulation: Indicated by parasutural ridges; gonyaulacacean, formula: ?7`, 6", 6c, 6```,1p, 1````, 1-3s; number of paraplates at apex not known with certainty, may include intercalaries.
Archaeopyle: At apex, type uncertain; exact outline of archaeopyle and operculum unknown.
Paracingulum: Indicated by six transversely elongate, rectangular paraplates.
Parasulcus: Outlined by parasutural ridges; longitudinally elongate, wide antapically, narrow and subdivided apically.
Size: Small.
Affinities:
Fibradinium differs from Microdinium in having a fibrous rather than a smooth or weakly ornamented autophragm.
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Emended description Vieira et al., 2025:
Emended diagnosis: Cysts subspherical; gonyaulacacean, paratabulation indicated by parasutural ridges, formula 5′, 5a, 7″, 6c, 7″’, 1p, 1″“.
Emended description: Cysts are small, subspherical, with a smaller epicyst than the hypocyst. The periphragm displays ridges and shallow penitabular indentations“. SEM analysis shows that the latter features form complete rings around some paraplates. The tabulation, determined through SEM, follows a pattern of 5’, 5a, 7”, 6c, 7″’, 1p, 1″“. The archeopyle is apical-intercalary (tAtI)a, with an operculum typically attached to the anterior sulcal paraplate.
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Fibradinium Morgenroth, 1968. Theca without processes, weakly ellipsoidal. Thecal wall composed of two layers of which the inner one is a smooth membrane, the outer one fibrous. Tabulation formula: ?7`, 6", 6c. 6"', 1p, 1"''. Cingulum equatorial, circular to weakly spiral to the left. Sulcus undifferentiated.