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Dissiliodinium
From Fensome et al., 2019:
Dissiliodinium, Drugg, 1978, p.67–68.
Emendations: Bailey and Partington, 1991, p.246; Feist-Burkhardt and Monteil, 2001, p.58,60,62.
Taxonomic junior synonyms: Okerisphaeridium, according to Feist-Burkhardt and Monteil (2001, p.58); Gongylodinium, by implication in Prauss (1989, p.38), who transferred the "type species" of Gongylodinium, Gongylodinium erymnoteichon, to Dissiliodinium -- however, Feist-Burkhardt and Monteil (1998, p.43; 2001, p.58) retained Gongylodinium.
Type: Drugg, 1978, pl.4, fig.5, as Dissiliodinium globulus.
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Original description: [Drugg, 1978]:
Diagnosis:
Cyst spherical to subspherical with a gonyaulacid epicystal paratabulation. Archaeopyle formed by loss of most of the precingular paraplates. Apical paraplates remain attached to the hypocyst via the parasulcal tongue and probably paraplate 6`` as well.
Affinities:
Dissiliodinium is related to the genera Leptodinium, Gonyaulacysta and Occisucysta. It differs from all in losing more precingular paraplates in archaeopyle formation and in lacking any obvious indication of hypocystal paratabulation.
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Modified description:
Stover and Williams 1987, p.85:
Synopsis:
Cysts proximate, subspherical; autophragm ornamented with features of low relief; archeopyle precingular, type 4P-5P, opercular pieces normally free; apical paraplates and probably paraplate 6" remain attached to hypocyst which lacks indications of paratabulation.
Description:
Shape: Subspherical.
Wall relationships: Autophragm only.
Wall features: No parasutural features. Autophragm variously ornamented with features of low relief.
Archeopyle: Precingular, compound, type 4P-5P, formed by the loss of paraplates 1"-5" or 2"-5"; opercular pieces normally free.
Paratabulation: Indicated on epicyst only and clearly evident only when precingular paraplates are separated completely or dislodged; paraplates of apical series not differentiated and attached to hypocyst, probably together with paraplate 6", by parasulcal tongue.
Paracingulum: Generally not indicated.
Parasulcus: Not indicated.
Size: Intermediate to large, about 55 to 115 µm.
Affinities:
Dissiliodinium differs from Lingulodinium Wall 1967 in lacking nontabular processes. Mancodinium Morgenroth 1970 differs from Dissiliodinium in having seven rather than six precingular paraplates and in possessing anterior intercalary paraplates as well. Lunatadinium Brideaux and McIntyre 1973 is reported as having a precingular 3P archaeopyle.
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Emended description:
Bailey and Partington, 1991:
Diagnosis:
Proximate subspherical gonyaulacoid dinocyst of intermediate to large size (50-110 micrometers). The autophragm is smooth, or more normally ornamented by nontabular features of low relief. The archaeopyle is variable precingular(type IP-5P),opercular pieces normally free.Apical plates and plate 6" remain attached to hypocyst. Epicystal tabulation derived from the outline of archaeopyle indicate formula; 4`, 0a, 6". Faint parasutures delineating the cingulum may rarely be observed. Hypocyst lacks any indication of tabulation.
Remarks:
Dissilioflinium is originally described with a type 4P-5P archaeopyle.The generic diagnosis is emended to include the variable 1P-5P archaeopyle and the absence of dorsal intercalary plates on the epicyst.
Affinities:
Dissiliodinium differs from Durotrigia Bailey (1987) in being non-tabulate and lacking dorsal intercalary plates on the epicyst.
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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.
Dissiliodinium Drugg, 1978. Drugg (1978, p.67) provided the following diagnosis, Cyst spherical to subspherical with a gonyaulacoid epicystal paratabulation. Archeopyle formed by the loss of most of the precingular paraplates. Apical plates remain attached to the hypocyst via the parasulcal tongue and probably paraplate 6" as well.
Dissiliodinium, Drugg, 1978, p.67–68.
Emendations: Bailey and Partington, 1991, p.246; Feist-Burkhardt and Monteil, 2001, p.58,60,62.
Taxonomic junior synonyms: Okerisphaeridium, according to Feist-Burkhardt and Monteil (2001, p.58); Gongylodinium, by implication in Prauss (1989, p.38), who transferred the "type species" of Gongylodinium, Gongylodinium erymnoteichon, to Dissiliodinium -- however, Feist-Burkhardt and Monteil (1998, p.43; 2001, p.58) retained Gongylodinium.
Type: Drugg, 1978, pl.4, fig.5, as Dissiliodinium globulus.
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Drugg, 1978]:
Diagnosis:
Cyst spherical to subspherical with a gonyaulacid epicystal paratabulation. Archaeopyle formed by loss of most of the precingular paraplates. Apical paraplates remain attached to the hypocyst via the parasulcal tongue and probably paraplate 6`` as well.
Affinities:
Dissiliodinium is related to the genera Leptodinium, Gonyaulacysta and Occisucysta. It differs from all in losing more precingular paraplates in archaeopyle formation and in lacking any obvious indication of hypocystal paratabulation.
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Modified description:
Stover and Williams 1987, p.85:
Synopsis:
Cysts proximate, subspherical; autophragm ornamented with features of low relief; archeopyle precingular, type 4P-5P, opercular pieces normally free; apical paraplates and probably paraplate 6" remain attached to hypocyst which lacks indications of paratabulation.
Description:
Shape: Subspherical.
Wall relationships: Autophragm only.
Wall features: No parasutural features. Autophragm variously ornamented with features of low relief.
Archeopyle: Precingular, compound, type 4P-5P, formed by the loss of paraplates 1"-5" or 2"-5"; opercular pieces normally free.
Paratabulation: Indicated on epicyst only and clearly evident only when precingular paraplates are separated completely or dislodged; paraplates of apical series not differentiated and attached to hypocyst, probably together with paraplate 6", by parasulcal tongue.
Paracingulum: Generally not indicated.
Parasulcus: Not indicated.
Size: Intermediate to large, about 55 to 115 µm.
Affinities:
Dissiliodinium differs from Lingulodinium Wall 1967 in lacking nontabular processes. Mancodinium Morgenroth 1970 differs from Dissiliodinium in having seven rather than six precingular paraplates and in possessing anterior intercalary paraplates as well. Lunatadinium Brideaux and McIntyre 1973 is reported as having a precingular 3P archaeopyle.
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Emended description:
Bailey and Partington, 1991:
Diagnosis:
Proximate subspherical gonyaulacoid dinocyst of intermediate to large size (50-110 micrometers). The autophragm is smooth, or more normally ornamented by nontabular features of low relief. The archaeopyle is variable precingular(type IP-5P),opercular pieces normally free.Apical plates and plate 6" remain attached to hypocyst. Epicystal tabulation derived from the outline of archaeopyle indicate formula; 4`, 0a, 6". Faint parasutures delineating the cingulum may rarely be observed. Hypocyst lacks any indication of tabulation.
Remarks:
Dissilioflinium is originally described with a type 4P-5P archaeopyle.The generic diagnosis is emended to include the variable 1P-5P archaeopyle and the absence of dorsal intercalary plates on the epicyst.
Affinities:
Dissiliodinium differs from Durotrigia Bailey (1987) in being non-tabulate and lacking dorsal intercalary plates on the epicyst.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Dissiliodinium Drugg, 1978. Drugg (1978, p.67) provided the following diagnosis, Cyst spherical to subspherical with a gonyaulacoid epicystal paratabulation. Archeopyle formed by the loss of most of the precingular paraplates. Apical plates remain attached to the hypocyst via the parasulcal tongue and probably paraplate 6" as well.