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Microdinium densigranulatum
From Fensome et al., 2019:
Microdinium densigranulatum (Below, 1987b, p.44–45, pl.13, figs.6–10; pl.14, figs.13–15) Lentin and Williams, 1989, p.244. Holotype: Below, 1987b, pl.13, figs.6–10; Fensome et al., 1993a, figs.1–5 — p.1119. Originally Phanerodinium, subsequently (and now) Microdinium. Age: middle–late Albian.
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Locus typicus: Between Wissant and Strouane, Boulonnais, France
Stratum typicum: Middle Albian
Translation Below, 1987: Fensome et al., 1993
Original description: Below, 1987b, p.45: Phanerodinium densigranulatum
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 proximate to proximochorate, acavate, spheroidal to ovaloidal, hypocyst twice as long as epicyst, equatorial section circular, maximum diameter at the posterior cingular margin; size small, wall composed of thin pedium and luxuria, which forms sometimes very densely packed granules or short baculi as well as low, finate ridges; the ridges comprise rows of distally fused setae and long baculi at close, but variable intervals; height of intraareate and finate ornaments very variable; areation formula NR PR/X PR, NR'/X', NRa/Xa, 7'', 7c, 6''', 2'''', as, NR FM/X FM, ls, rs, ps; areation absent or rudimentary on apical and anterior intercalary regions; 7 precingulars, 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" characteristically dorsal, anteriorly geniculate V-nE 5" (R), anteriorly geniculate V-nE 6" (VR), small anteriorly geniculate V-nE 7" (VVR); cingulum level, very slightly helicoid laevorotatory, 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, non-partite or small VI as, small oval FM not, or 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' + la + 2a + 3a + 4a; operculum foederate, adnate, general opercular formula (PR + 1' + 2' + 3' + 4' + 1a + 2a + 3a + 4a).
Size: Holotype: length 34 µm, breadth 29 µm, thickness 27 µm.
Microdinium densigranulatum (Below, 1987b, p.44–45, pl.13, figs.6–10; pl.14, figs.13–15) Lentin and Williams, 1989, p.244. Holotype: Below, 1987b, pl.13, figs.6–10; Fensome et al., 1993a, figs.1–5 — p.1119. Originally Phanerodinium, subsequently (and now) Microdinium. Age: middle–late Albian.
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Locus typicus: Between Wissant and Strouane, Boulonnais, France
Stratum typicum: Middle Albian
Translation Below, 1987: Fensome et al., 1993
Original description: Below, 1987b, p.45: Phanerodinium densigranulatum
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 proximate to proximochorate, acavate, spheroidal to ovaloidal, hypocyst twice as long as epicyst, equatorial section circular, maximum diameter at the posterior cingular margin; size small, wall composed of thin pedium and luxuria, which forms sometimes very densely packed granules or short baculi as well as low, finate ridges; the ridges comprise rows of distally fused setae and long baculi at close, but variable intervals; height of intraareate and finate ornaments very variable; areation formula NR PR/X PR, NR'/X', NRa/Xa, 7'', 7c, 6''', 2'''', as, NR FM/X FM, ls, rs, ps; areation absent or rudimentary on apical and anterior intercalary regions; 7 precingulars, 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" characteristically dorsal, anteriorly geniculate V-nE 5" (R), anteriorly geniculate V-nE 6" (VR), small anteriorly geniculate V-nE 7" (VVR); cingulum level, very slightly helicoid laevorotatory, 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, non-partite or small VI as, small oval FM not, or 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' + la + 2a + 3a + 4a; operculum foederate, adnate, general opercular formula (PR + 1' + 2' + 3' + 4' + 1a + 2a + 3a + 4a).
Size: Holotype: length 34 µm, breadth 29 µm, thickness 27 µm.