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Microdinium angulare
Microdinium angulare (Below, 1987) Lentin and Williams, 1989
Originally Phanerodinium, subsequently (and now) Microdinium.
Holotype: Below, 1987, pl.13, figs.11-15
Locus typicus: Old "Morgenstern" iron ore open pit mine Hahndorf, Germany
Stratum typicum: Middle Albian
Translation Below, 1987: Fensome et al., 1993
Original description: Below, 1987, p.39: Phanerodinium angulare
Arrangement of vesicles/plates on the dinoflagellate amphiesma cop, pop, cap, 4", 4a, 7", 7c, 6""", 2"""", as, FM subdivided into several periflagellar areae, ls, rs, ps; pentagonal 1"""" and hexagonal 2"""" partiform; omegaform ps very large; adelopore on suture 1"/4"; primtegulate epithecal series connected sinistrally with as; growth gonyaulacoid.
Cyst form proximate-proxichomorate, polyhedral, epicyst tholiform with flattened apex to coniform, hypocyst twice as long with steep flanks to nearly prismatic, tentoriate, equatorial section oval to lenticular, maximum diameter at the posterior cingular margin, size small; wall composed of thin pedium and prismatically structured luxuria with a coarse-grained, densely baculate, or secate surface; the luxuria forms low, distally glabrous or even irregularly notched, denticulate, finate ridges, and on the hypocyst, especially around the apex, broad-based spinules in gonal locations; between apical and anterior intercalary areae, finate ridges are absent; areation formula NR/PR, NR"/X", NRa/Xa, 7", 7c, 6""", 2"""", Xs/as, FM, ls, rs, ps; PR, very small apicals and anterior intercalaries not differentiated; 7 postcingulars, anteriorly geniculate V-nE 1" (VVL), anteriorly geniculate VnE 2n (L), anteriorly geniculate V-nE 3" (DDL), anteriorly geniculate V-nE 4" (DDR), finis 3"/4" often located dorsally, anteriorly geniculate V-nE 5" (R), anteriorly geniculate V-nE 6" (VR), small anteriorly geniculate V-nE 7" (VVR), cingulum approximately planispiral, not, or only shallowly, indented, heptapartite, lati 1c to 6c, isofastigiate 7c; 6 postcingulars, posteriorly linear V-nE 1""" (VVL), posteriorly linear IV-nE 2""" (VL), posteriorly geniculate VnE 3""" (DL), posteriorly linear IV-nE 4""" (DDR), posteriorly linear IV-nE 5"" (R), posteriorly linear V-nE 6n" (VR); 2 antapicals partiform, V 1"""" descending towards VL, VI 2""" descending towards R; sulcus not indented, central sulcus usually reflected rudimentarily, areae as and FM nonfinate towards 1", 7", 1c and 7c, or as finate, small oval FM not, or rudimentarily, subdivided into very small areae, small V ls, small V rs, large omegaform VI ps; archeopyle apical/anterior intercalary, PR + 1" + 2" + 3" + 4" + 1a + 2a + 3a + 4a; operculum foederate, adnate, general opercular formula (PR + 1" + 2"+ 4" + 1a + 2a + 3a + 4a)a.
Size: Holotype: length 40 µm, breadth 34 µm, thickness 26 µm.
Originally Phanerodinium, subsequently (and now) Microdinium.
Holotype: Below, 1987, pl.13, figs.11-15
Locus typicus: Old "Morgenstern" iron ore open pit mine Hahndorf, Germany
Stratum typicum: Middle Albian
Translation Below, 1987: Fensome et al., 1993
Original description: Below, 1987, p.39: Phanerodinium angulare
Arrangement of vesicles/plates on the dinoflagellate amphiesma cop, pop, cap, 4", 4a, 7", 7c, 6""", 2"""", as, FM subdivided into several periflagellar areae, ls, rs, ps; pentagonal 1"""" and hexagonal 2"""" partiform; omegaform ps very large; adelopore on suture 1"/4"; primtegulate epithecal series connected sinistrally with as; growth gonyaulacoid.
Cyst form proximate-proxichomorate, polyhedral, epicyst tholiform with flattened apex to coniform, hypocyst twice as long with steep flanks to nearly prismatic, tentoriate, equatorial section oval to lenticular, maximum diameter at the posterior cingular margin, size small; wall composed of thin pedium and prismatically structured luxuria with a coarse-grained, densely baculate, or secate surface; the luxuria forms low, distally glabrous or even irregularly notched, denticulate, finate ridges, and on the hypocyst, especially around the apex, broad-based spinules in gonal locations; between apical and anterior intercalary areae, finate ridges are absent; areation formula NR/PR, NR"/X", NRa/Xa, 7", 7c, 6""", 2"""", Xs/as, FM, ls, rs, ps; PR, very small apicals and anterior intercalaries not differentiated; 7 postcingulars, anteriorly geniculate V-nE 1" (VVL), anteriorly geniculate VnE 2n (L), anteriorly geniculate V-nE 3" (DDL), anteriorly geniculate V-nE 4" (DDR), finis 3"/4" often located dorsally, anteriorly geniculate V-nE 5" (R), anteriorly geniculate V-nE 6" (VR), small anteriorly geniculate V-nE 7" (VVR), cingulum approximately planispiral, not, or only shallowly, indented, heptapartite, lati 1c to 6c, isofastigiate 7c; 6 postcingulars, posteriorly linear V-nE 1""" (VVL), posteriorly linear IV-nE 2""" (VL), posteriorly geniculate VnE 3""" (DL), posteriorly linear IV-nE 4""" (DDR), posteriorly linear IV-nE 5"" (R), posteriorly linear V-nE 6n" (VR); 2 antapicals partiform, V 1"""" descending towards VL, VI 2""" descending towards R; sulcus not indented, central sulcus usually reflected rudimentarily, areae as and FM nonfinate towards 1", 7", 1c and 7c, or as finate, small oval FM not, or rudimentarily, subdivided into very small areae, small V ls, small V rs, large omegaform VI ps; archeopyle apical/anterior intercalary, PR + 1" + 2" + 3" + 4" + 1a + 2a + 3a + 4a; operculum foederate, adnate, general opercular formula (PR + 1" + 2"+ 4" + 1a + 2a + 3a + 4a)a.
Size: Holotype: length 40 µm, breadth 34 µm, thickness 26 µm.