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Microdinium septofibrosum
Microdinium septofibrosum (Below, 1987) Lentin and Williams, 1989
Originally Phanerodinium, subsequently (and now) Microdinium.
Holotype: Below, 1987, pl.13, figs.1-5; Fensome et al., 1993, p.1337, figs.1-5
Locus typicus: Old "Morgenstern" iron ore open pit mine, Hahndorf, Germany
Stratum typicum: Late Albian
Translation Below, 1987: Fensome et al., 1993
Original description: Below, 1987, p.52-53: Phanerodinium septofibrosum
Arrangement of vesicles/plates on the dinoflagellate amphiesma cop, pop, cap, 4", 4a, 7", 7c, 6""", 2"""", as, FM subdivided into several periflagellar platelets, ls, rs, ps; pentagonal 1"""" and hexagonal 2"""" partiform; omegaform ps very large; adelopore on suture 1"/4"; growth of plates gonyaulacoid.
Cyst form proximochorate, acavate, epicyst shallowly tholiform, hypocyst approximately three times as long as the epicyst, polyhedral, almost prismatic with steep flanks, antapex roof-shaped, maximal diameter at the posterior cingular margin, equatorial section circular, size small; wall composed of thin pedium and luxuria, luxuria forming high, fibrose, finate septa, and on the epicyst densely packed intraareate granules and baculi, hypocystal surface scabrate to glabrous; areation formula XPR/cop, pop, cap, 4", 4a, 7", 7c, 6""", 2"""", as, FM, ls, rs, ps; PR usually undifferentiated; 4 small apicals, steno VII 1" (V), VIII 2" (L), VIII 3" (R), steno V 4" (VVR); 4 small anterior intercalaries, caroidal la (DL), fastigiate 2a (D), deltaform inverse camerate 3a (DR), V 4a (RVR); 7 precingulars, anteriorly geniculate V-nE 1 (VVL), anteriorly geniculate V-nE 2" (L), anteriorly geniculate V-nE 3" (DDL), anteriorly geniculate V-nE 4" (DDR), finis 3"/4" approximately dorsal, anteriorly geniculate V-nE 5" (R), anteriorly geniculate V-nE 6" (VR), small anteriorly geniculate V-nE 7" (VVR); cingulum weakly helicoid laevorotatory to planispiral, indented, heptapartite, lati 1c to 6c, isofastigiate 7c; 6 postcingulars, posteriorly linear V-nE 1""" (VVL), posteriorly linear IV-nE 2""" (VL), posteriorly geniculate V-nE 3""" (DL), posteriorly linear IV-nE 4""" (DDR), posteriorly linear IV-nE 5""" (R), posteriorly linear V-nE 6""" (VR); 2 antapicals partiform, V 1"""" descending towards VL, VI 2"""" towards R; sulcus level, partite, small VI as, small oval FM not, or only rudimentarily, subdivided into several 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" + 3" + 4" + 1a + 2a + 3a + 4a)[a].
Size: Holotype: length 35 Ám, breadth 31 Ám, thickness 30 Ám.
Originally Phanerodinium, subsequently (and now) Microdinium.
Holotype: Below, 1987, pl.13, figs.1-5; Fensome et al., 1993, p.1337, figs.1-5
Locus typicus: Old "Morgenstern" iron ore open pit mine, Hahndorf, Germany
Stratum typicum: Late Albian
Translation Below, 1987: Fensome et al., 1993
Original description: Below, 1987, p.52-53: Phanerodinium septofibrosum
Arrangement of vesicles/plates on the dinoflagellate amphiesma cop, pop, cap, 4", 4a, 7", 7c, 6""", 2"""", as, FM subdivided into several periflagellar platelets, ls, rs, ps; pentagonal 1"""" and hexagonal 2"""" partiform; omegaform ps very large; adelopore on suture 1"/4"; growth of plates gonyaulacoid.
Cyst form proximochorate, acavate, epicyst shallowly tholiform, hypocyst approximately three times as long as the epicyst, polyhedral, almost prismatic with steep flanks, antapex roof-shaped, maximal diameter at the posterior cingular margin, equatorial section circular, size small; wall composed of thin pedium and luxuria, luxuria forming high, fibrose, finate septa, and on the epicyst densely packed intraareate granules and baculi, hypocystal surface scabrate to glabrous; areation formula XPR/cop, pop, cap, 4", 4a, 7", 7c, 6""", 2"""", as, FM, ls, rs, ps; PR usually undifferentiated; 4 small apicals, steno VII 1" (V), VIII 2" (L), VIII 3" (R), steno V 4" (VVR); 4 small anterior intercalaries, caroidal la (DL), fastigiate 2a (D), deltaform inverse camerate 3a (DR), V 4a (RVR); 7 precingulars, anteriorly geniculate V-nE 1 (VVL), anteriorly geniculate V-nE 2" (L), anteriorly geniculate V-nE 3" (DDL), anteriorly geniculate V-nE 4" (DDR), finis 3"/4" approximately dorsal, anteriorly geniculate V-nE 5" (R), anteriorly geniculate V-nE 6" (VR), small anteriorly geniculate V-nE 7" (VVR); cingulum weakly helicoid laevorotatory to planispiral, indented, heptapartite, lati 1c to 6c, isofastigiate 7c; 6 postcingulars, posteriorly linear V-nE 1""" (VVL), posteriorly linear IV-nE 2""" (VL), posteriorly geniculate V-nE 3""" (DL), posteriorly linear IV-nE 4""" (DDR), posteriorly linear IV-nE 5""" (R), posteriorly linear V-nE 6""" (VR); 2 antapicals partiform, V 1"""" descending towards VL, VI 2"""" towards R; sulcus level, partite, small VI as, small oval FM not, or only rudimentarily, subdivided into several 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" + 3" + 4" + 1a + 2a + 3a + 4a)[a].
Size: Holotype: length 35 Ám, breadth 31 Ám, thickness 30 Ám.