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Dollidinium
From Williams et al., 2017:
[Dollidinium, Helby and Stover, 1987b, p. 159-160
Type Species: as Palaeostomocystis sinuosa, Cookson and Eisenack, 1960b (pl.38, fig.16), lectotype:
Dollidinium sinuosum, emend. Helby and Stover, 1987]
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Original description: [Helby and Stover , 1987]:
Synopsis:
Cysts proximate, normally compressed dorsoventrally, hexalobate with two lateral lobes and a polar lobe on both epicyst and hypocyst; body consists of autophragm or two closely appressed layers which may be separated locally, individual paraplates not indicated or delimited completely or nearly so by parasutural features- paratabulation formula: 0-2pr, 6`, 0a, 6``, 6c, 6```, 1p, 2``, Xs; archeopyle apical, atypical, formed on the dorsal surface, offset, involving paraplates 3` and 4`; operculum free.
Description:
Shape: Hexalobate in dorsal ventral view, commonly compressed; epicyst with an apical and two lateral lobes, hypocyst with an antapical and two lateral lobes; equatorial area constricted.
Wall Relationships: Autophragm, or two closely appressed wall layers, which may be separated locally, particularly on the lateral lobes.
Wall features: Surface smooth to faintly ornamented with features of low relief; low parasutural ridges may be present.
Archeopyle: Apical, atypical, type 2A; opening subcircular and offset from middorsal axis, including most of paraplates 3` and 4`; operculum free, isolated opercula unobserved.
Paratabulation: Expressed by the archeopyle only or by it in conjunction with parasutural features which may be nearly complete;
formula, when indicated by parasutural features: 0-2pr, 6`, 0a, 6``, 6c, 6```, 1p, 2````, Xs.
Paracingulum: Position reflected by constriction in equatorial area and may be indicated additionally by parasutural features outlining six subrectangular paraplates.
Parasulcus: Not delimited, or expressed by marginal parasutural ridges; a relatively large posterior sulcal paraplate may be differentiated.
Size: Small to intermediate.
[Dollidinium, Helby and Stover, 1987b, p. 159-160
Type Species: as Palaeostomocystis sinuosa, Cookson and Eisenack, 1960b (pl.38, fig.16), lectotype:
Dollidinium sinuosum, emend. Helby and Stover, 1987]
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Helby and Stover , 1987]:
Synopsis:
Cysts proximate, normally compressed dorsoventrally, hexalobate with two lateral lobes and a polar lobe on both epicyst and hypocyst; body consists of autophragm or two closely appressed layers which may be separated locally, individual paraplates not indicated or delimited completely or nearly so by parasutural features- paratabulation formula: 0-2pr, 6`, 0a, 6``, 6c, 6```, 1p, 2``, Xs; archeopyle apical, atypical, formed on the dorsal surface, offset, involving paraplates 3` and 4`; operculum free.
Description:
Shape: Hexalobate in dorsal ventral view, commonly compressed; epicyst with an apical and two lateral lobes, hypocyst with an antapical and two lateral lobes; equatorial area constricted.
Wall Relationships: Autophragm, or two closely appressed wall layers, which may be separated locally, particularly on the lateral lobes.
Wall features: Surface smooth to faintly ornamented with features of low relief; low parasutural ridges may be present.
Archeopyle: Apical, atypical, type 2A; opening subcircular and offset from middorsal axis, including most of paraplates 3` and 4`; operculum free, isolated opercula unobserved.
Paratabulation: Expressed by the archeopyle only or by it in conjunction with parasutural features which may be nearly complete;
formula, when indicated by parasutural features: 0-2pr, 6`, 0a, 6``, 6c, 6```, 1p, 2````, Xs.
Paracingulum: Position reflected by constriction in equatorial area and may be indicated additionally by parasutural features outlining six subrectangular paraplates.
Parasulcus: Not delimited, or expressed by marginal parasutural ridges; a relatively large posterior sulcal paraplate may be differentiated.
Size: Small to intermediate.