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Dodekovia bullula
Dodekovia bullula (Bjaerke, 1980) Below, 1987
Now Parvocysta. Originally (and now) Paruocysta, subsequently Dodekovia.
At the time of the transfer, Below, 1987, presented a modified description for this species.
Lentin and Williams, 1989, retained the species in Parvocysta Bjaerke, 1980.
Holotype: Bjaerke, 1980, pl.1, fig.4-5
Locus typicus: Svalbard IV, Spitzbergen
Stratum typicum: Toarcian
Translation Below, 1987: Translation Bureau, Secretary of State Canada, 1988
Original diagnosis: Bjaerke 1980, p.62: Parvocysta bullula
Dinoflagellate cysts of the genus Parvocysta with a subcircular to pentagonal outline. Apical area sometimes narrowing into a short, blunt, apical protrusion. Surface ornamented with blunt processes less than 1 Ám high. Paracingulum indicated by a shallow equatorial depression. Size: 22-35 Ám long, 20-31 Ám wide.
Original description: Bjaerke 1980, p. 64: Parvocysta bullula
Small dinoflagellate cysts with a subspherical to pentagonal outline, apex slightly pointed, antapex broadly rounded to flat. Cyst wall single layered, ornamented with blunt processes less than 1 Ám high producing a scabrate appearance. Paratabulation except for archaeopyle not observed. Archaeopyle intercalary, outline hexagonal with posterior and anterior angulations (geniculate), formed by one middorsal paraplate. Operculum in place in most specimens and difficult to distinguish. Paracingulum indicated by a shallow equatorial depression. Parasulcus seen in some specimens as a shallow depression extending towards the antapical area.
Modified description: Below, 1987, p. 115
Arrangement of vesicles/plates on the dinoflagellate amphiesma cop, pop, cap, 5", 3a, 7"", 7c, 5""", 2"""", as, z, y, ps; 1"""" and 2"""" located symmetrically on either side of the dorsoventral plane. Cystic habit proximate, acavate, peridinoidal, epicyst acute coniform, also produced into a short apical horn and widely expanded at the cingulum, sometimes in a wing-like shape, cingulum deeply indented dorsally facing the epicyst and fused with the postcingular region of the hypocyst into a hyperboloid sector, antapex flattened, equatorial cross section lenticular, reniform; size small; wall composed of smooth pedium which is folded into striking lonaitudinally finate, low, distally rounded or angular ribs round the apical and antapical areae and on the dextro- and sinistrolateral flanks of the cyst between the apex and the antapex; areation schematically indicated, without the outlines of the
areae being visible; areation formula NR PR/cop, pop, cap, NR"/NR1", X2", X3", X4", NRS", NR1a, fastigiate or heptagonal 2a(arch), NR3a, NR"", Xc, cingulum planar without posterior margin, NR""", X1"""", X2"""", NRs/Xs; archaeopyle anterior intercalary, 2a; operculum monoareate, secate, opercular formula 2a(s).
Affinities:
Bjµrke, 1980, p. 65: Parvocysta bullula
Parvocysta bullula differs from Parvocysta contracta, in that the latter has a characteristic equatorial constriction and a more elongated outline.
Now Parvocysta. Originally (and now) Paruocysta, subsequently Dodekovia.
At the time of the transfer, Below, 1987, presented a modified description for this species.
Lentin and Williams, 1989, retained the species in Parvocysta Bjaerke, 1980.
Holotype: Bjaerke, 1980, pl.1, fig.4-5
Locus typicus: Svalbard IV, Spitzbergen
Stratum typicum: Toarcian
Translation Below, 1987: Translation Bureau, Secretary of State Canada, 1988
Original diagnosis: Bjaerke 1980, p.62: Parvocysta bullula
Dinoflagellate cysts of the genus Parvocysta with a subcircular to pentagonal outline. Apical area sometimes narrowing into a short, blunt, apical protrusion. Surface ornamented with blunt processes less than 1 Ám high. Paracingulum indicated by a shallow equatorial depression. Size: 22-35 Ám long, 20-31 Ám wide.
Original description: Bjaerke 1980, p. 64: Parvocysta bullula
Small dinoflagellate cysts with a subspherical to pentagonal outline, apex slightly pointed, antapex broadly rounded to flat. Cyst wall single layered, ornamented with blunt processes less than 1 Ám high producing a scabrate appearance. Paratabulation except for archaeopyle not observed. Archaeopyle intercalary, outline hexagonal with posterior and anterior angulations (geniculate), formed by one middorsal paraplate. Operculum in place in most specimens and difficult to distinguish. Paracingulum indicated by a shallow equatorial depression. Parasulcus seen in some specimens as a shallow depression extending towards the antapical area.
Modified description: Below, 1987, p. 115
Arrangement of vesicles/plates on the dinoflagellate amphiesma cop, pop, cap, 5", 3a, 7"", 7c, 5""", 2"""", as, z, y, ps; 1"""" and 2"""" located symmetrically on either side of the dorsoventral plane. Cystic habit proximate, acavate, peridinoidal, epicyst acute coniform, also produced into a short apical horn and widely expanded at the cingulum, sometimes in a wing-like shape, cingulum deeply indented dorsally facing the epicyst and fused with the postcingular region of the hypocyst into a hyperboloid sector, antapex flattened, equatorial cross section lenticular, reniform; size small; wall composed of smooth pedium which is folded into striking lonaitudinally finate, low, distally rounded or angular ribs round the apical and antapical areae and on the dextro- and sinistrolateral flanks of the cyst between the apex and the antapex; areation schematically indicated, without the outlines of the
areae being visible; areation formula NR PR/cop, pop, cap, NR"/NR1", X2", X3", X4", NRS", NR1a, fastigiate or heptagonal 2a(arch), NR3a, NR"", Xc, cingulum planar without posterior margin, NR""", X1"""", X2"""", NRs/Xs; archaeopyle anterior intercalary, 2a; operculum monoareate, secate, opercular formula 2a(s).
Affinities:
Bjµrke, 1980, p. 65: Parvocysta bullula
Parvocysta bullula differs from Parvocysta contracta, in that the latter has a characteristic equatorial constriction and a more elongated outline.