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Desmocysta californica
From Fensome et al., 2019:
Desmocysta californica Monteil, 1992a, p.279,281, pl.5, figs.1–9; pl.8, figs.1–4.
Emendation: Duxbury 2018, p.180, as Desmocysta californica. Holotype: Monteil, 1992a, pl.5, figs.1–2.
NOW Desmocysta. Originally Warrenia, subsequently (and now) Desmocysta.
Age: late Tithonian–early Valanginian.
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Original diagnosis: Monteil, 1992, p. 279 (identical to that of the genus)
Synopsis: Cyst proximate to proximochorate, acavate, ovoidal, with or without antapical filaments; ornamentation smooth, finely granular, coarsely verrucate with anastomosing elements, or spinous; paratabulation gonyaulacoid, indicated by the archaeopyle only and/or partially to completely expressed by the penitabular/ intratabular ornamentation; formula: ?1-2 pr, 4', 0a, 6'', 6c, 6''', 1p, 1'''', s; archaeopyle precingular, type 2P (3''+4''). Operculum consisting of two free opercular pieces.
Diagnosis:
Shape: Cyst proximate to proximochorate, acavate, ovoidal with or without antapical filaments. Apex and/or antapex sometimes marked by a slight bulge. In the spinous forms, the apex may be accented by a group of small spines.
Wall structure: Autophragm only.
Wall features: Ornamentation smooth, finely granular, coarsely verrucate with anastomosing elements or spinous.
Archaeopyle: Precingular, type 2P (3''+4''). Operculum consisting of two free opercular pieces.
Paratabulation: Indicated by the archaeopyle margin only and/or partially to completely expressed by the penitabular/intratabular ornamentation; gonyaulacoid, formula: ?1-2pr, 4', 0a, 6'', 6c, 6''', 1p, 1'''', s.
Paracingulum: Not indicated or clearly indicated by the ornamentation.
Parasulcus: Not indicated or sulcal area delimited by an absence and/or reduction of the ornamentation.
Size: Small, about 30-40 µm long.
Dimensions:
Holotype: length x width of the cyst (exclusive of ornamentation) = 46 x 39 µm, ornamentation varying from 1 to 2.5 µm.
Variation (12 specimens): length x width of the cyst (exclusive of ornamentation) = 41-50 x 32-44 µm, ornamentation varying from 1 to 2.5 µm.
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Emendation (Duxbury, 2018):
Emended Diagnosis: A thin-walled, spheroidal to ovoidal dinoflagellate cyst species with a two plate precingular archeopyle. The surface is covered with granules/verrucae which may vary in size between specimens, and which can show occasional alignment. A large number of fine filaments are usually present, extending from a small area at the antapex and varying in length between specimens. The filaments are normally separated from each other, but may be tangled to varying degrees.
Dimensions: Cyst 58 (48) 43 µm × 51 (41) 35 µm.
Antapical filaments 51 (35) 25 µm.
Specimens Measured: 8.
Remarks: The presence of surface granules/verrucae separates this species from others in the genus. Both Desmocysta plekta and Desmocysta simplex are smooth-walled and D. simplex possesses markedly fewer antapical filaments. Although Monteil (1992, p. 279) included smooth forms and those with spinose ornament within this species, the diagnosis is emended here to include only granular/verrucate forms, comparable to Monteil’s (op. cit.) type material. No spinose forms were encountered in the present study and such forms might be considered as a separate species. Desmocysta californica occurs between Beds D7C and D4C at Speeton, Berriasian to lower Valanginian.
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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.
Warrenia californica Monteil, 1994, is a proximate to proximochorate ovoidal cyst with or without antapical filaments. Ornamentation smooth, finely granulate, or strongly verrucate with anastomosing elements or spines. Paratabulation gonyaulacoid, indicated only by archeopyle and partly be penitabulate or intratabular ornamentation. Formula 1-2pr, 4', 0a, 6", 6c, 6"’, 1p, 1"”, s. Archeopyle formed from loss of 3" and 4". Two free opercular pieces. Size: length and width, excluding ornament 41-50 x 32-44 µm, ornamentation 1-2.5 µm.
Desmocysta californica Monteil, 1992a, p.279,281, pl.5, figs.1–9; pl.8, figs.1–4.
Emendation: Duxbury 2018, p.180, as Desmocysta californica. Holotype: Monteil, 1992a, pl.5, figs.1–2.
NOW Desmocysta. Originally Warrenia, subsequently (and now) Desmocysta.
Age: late Tithonian–early Valanginian.
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Original diagnosis: Monteil, 1992, p. 279 (identical to that of the genus)
Synopsis: Cyst proximate to proximochorate, acavate, ovoidal, with or without antapical filaments; ornamentation smooth, finely granular, coarsely verrucate with anastomosing elements, or spinous; paratabulation gonyaulacoid, indicated by the archaeopyle only and/or partially to completely expressed by the penitabular/ intratabular ornamentation; formula: ?1-2 pr, 4', 0a, 6'', 6c, 6''', 1p, 1'''', s; archaeopyle precingular, type 2P (3''+4''). Operculum consisting of two free opercular pieces.
Diagnosis:
Shape: Cyst proximate to proximochorate, acavate, ovoidal with or without antapical filaments. Apex and/or antapex sometimes marked by a slight bulge. In the spinous forms, the apex may be accented by a group of small spines.
Wall structure: Autophragm only.
Wall features: Ornamentation smooth, finely granular, coarsely verrucate with anastomosing elements or spinous.
Archaeopyle: Precingular, type 2P (3''+4''). Operculum consisting of two free opercular pieces.
Paratabulation: Indicated by the archaeopyle margin only and/or partially to completely expressed by the penitabular/intratabular ornamentation; gonyaulacoid, formula: ?1-2pr, 4', 0a, 6'', 6c, 6''', 1p, 1'''', s.
Paracingulum: Not indicated or clearly indicated by the ornamentation.
Parasulcus: Not indicated or sulcal area delimited by an absence and/or reduction of the ornamentation.
Size: Small, about 30-40 µm long.
Dimensions:
Holotype: length x width of the cyst (exclusive of ornamentation) = 46 x 39 µm, ornamentation varying from 1 to 2.5 µm.
Variation (12 specimens): length x width of the cyst (exclusive of ornamentation) = 41-50 x 32-44 µm, ornamentation varying from 1 to 2.5 µm.
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Emendation (Duxbury, 2018):
Emended Diagnosis: A thin-walled, spheroidal to ovoidal dinoflagellate cyst species with a two plate precingular archeopyle. The surface is covered with granules/verrucae which may vary in size between specimens, and which can show occasional alignment. A large number of fine filaments are usually present, extending from a small area at the antapex and varying in length between specimens. The filaments are normally separated from each other, but may be tangled to varying degrees.
Dimensions: Cyst 58 (48) 43 µm × 51 (41) 35 µm.
Antapical filaments 51 (35) 25 µm.
Specimens Measured: 8.
Remarks: The presence of surface granules/verrucae separates this species from others in the genus. Both Desmocysta plekta and Desmocysta simplex are smooth-walled and D. simplex possesses markedly fewer antapical filaments. Although Monteil (1992, p. 279) included smooth forms and those with spinose ornament within this species, the diagnosis is emended here to include only granular/verrucate forms, comparable to Monteil’s (op. cit.) type material. No spinose forms were encountered in the present study and such forms might be considered as a separate species. Desmocysta californica occurs between Beds D7C and D4C at Speeton, Berriasian to lower Valanginian.
------------------------------------------------------------------------------------------------------------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Warrenia californica Monteil, 1994, is a proximate to proximochorate ovoidal cyst with or without antapical filaments. Ornamentation smooth, finely granulate, or strongly verrucate with anastomosing elements or spines. Paratabulation gonyaulacoid, indicated only by archeopyle and partly be penitabulate or intratabular ornamentation. Formula 1-2pr, 4', 0a, 6", 6c, 6"’, 1p, 1"”, s. Archeopyle formed from loss of 3" and 4". Two free opercular pieces. Size: length and width, excluding ornament 41-50 x 32-44 µm, ornamentation 1-2.5 µm.