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Parvulodinium
From Williams et al., 2017:
[Parvulodinium, Dodekova, 1975, p. 29
Type species: Parvulodinium penitabulatum, Dedekova, 1975 (pl.6, figs.6–9)]
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Original description: [Dodekova, 1975]:
Description:
Ovoidal proximate cyst. The wall is two-layered, smooth homogeneous endophragm and thick fibrous periphragm. The latter makes up the ornamentation, represented by
granules, spines, clavate processes. The ornamentation elements are grouped in fields which determine the tabulation--?4`, 0-1a, 6", 6```, 1p, 1````. The sutures and the furrows are deprived of ornamentation or have shagreenate, scabrate, granulate, reticulate or foveolate surface. The cingulum is broad, almost round or slightly helicoidal and lies on the superior half of the body. The sulcus is broad and extends from the base of the epitract to the antapex. The epitract takes 1/3 or 1/4 of the overall length of the cyst. At the point of intersection of the two furrows a flagellar mark is present. The archaeopyle is apical with zig-zag margin.
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Modified description:
Stover and Evitt, 1978, p. 72-73:
Synopsis:
Cysts proximochorate; body ellipsoidal with intratabular clusters of granules, spines, or clavate processes separated by smooth areas or areas with features of low relief; endophragm and thicker periphragm in close contact. Paratabulation gonyaulacacean, indicated by parasutural features; archeopyle apical, Type (tA).
Description:
Shape: Body ellipsoidal.
Wall relationships: Layers in close contact; endophragm smooth; thicker fibrous periphragm forms ornamentation.
Wall features: No clearly delineated parasutural features; surface with intratabular clusters of granules, spines, or clavate processes separated by unornamented areas or areas with features of low relief.
Paratabulation: Indicated by intratabular features; gonyaulacacean, formula: ?4`, 0-1a, 6", Xc, 6```, 1p, 1````.
Archeopyle: Apical, Type (tA); principal archeopyle suture angular; operculum free.
Paracingulum: Expressed as relatively wide, mainly unornamented transverse band that divides the cyst unequally; epicyst much smaller than hypocyst.
Parasulcus: Nearly unornamented longitudinal area that widens antapically.
Size: Small.
Affinities:
Parvulodinium differs from Sentusidinium in having the ornamentation arranged in intratabular clusters rather than being nontabular.
[Parvulodinium, Dodekova, 1975, p. 29
Type species: Parvulodinium penitabulatum, Dedekova, 1975 (pl.6, figs.6–9)]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Dodekova, 1975]:
Description:
Ovoidal proximate cyst. The wall is two-layered, smooth homogeneous endophragm and thick fibrous periphragm. The latter makes up the ornamentation, represented by
granules, spines, clavate processes. The ornamentation elements are grouped in fields which determine the tabulation--?4`, 0-1a, 6", 6```, 1p, 1````. The sutures and the furrows are deprived of ornamentation or have shagreenate, scabrate, granulate, reticulate or foveolate surface. The cingulum is broad, almost round or slightly helicoidal and lies on the superior half of the body. The sulcus is broad and extends from the base of the epitract to the antapex. The epitract takes 1/3 or 1/4 of the overall length of the cyst. At the point of intersection of the two furrows a flagellar mark is present. The archaeopyle is apical with zig-zag margin.
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Modified description:
Stover and Evitt, 1978, p. 72-73:
Synopsis:
Cysts proximochorate; body ellipsoidal with intratabular clusters of granules, spines, or clavate processes separated by smooth areas or areas with features of low relief; endophragm and thicker periphragm in close contact. Paratabulation gonyaulacacean, indicated by parasutural features; archeopyle apical, Type (tA).
Description:
Shape: Body ellipsoidal.
Wall relationships: Layers in close contact; endophragm smooth; thicker fibrous periphragm forms ornamentation.
Wall features: No clearly delineated parasutural features; surface with intratabular clusters of granules, spines, or clavate processes separated by unornamented areas or areas with features of low relief.
Paratabulation: Indicated by intratabular features; gonyaulacacean, formula: ?4`, 0-1a, 6", Xc, 6```, 1p, 1````.
Archeopyle: Apical, Type (tA); principal archeopyle suture angular; operculum free.
Paracingulum: Expressed as relatively wide, mainly unornamented transverse band that divides the cyst unequally; epicyst much smaller than hypocyst.
Parasulcus: Nearly unornamented longitudinal area that widens antapically.
Size: Small.
Affinities:
Parvulodinium differs from Sentusidinium in having the ornamentation arranged in intratabular clusters rather than being nontabular.