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Evansia polyedrica
From Fensome et al., 2019:
Evansia polyedrica Below, 1990, p.76,78, pl.18, figs.1–4,13; text-figs.22a–e. Holotype: Below, 1990, pl.18, figs.1–4,13. Contrary to the opinion of Lentin and Williams (1993, p.215), this name is validly published. Below (1987a, p.6) stated that, unless otherwise indicated, all the material is in his personal collection. Since Below (1987a, 1987b, 1990) are parts I to III of a single study, we agree with J. Jansonius (personal communication) that Below's (1987a) repository statement refers to all three publications, fulfilling the requirement of ICN Article 40.7. Age: late Toarcian.
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Original description Below, 1990:
Derivatio nominis: named after the polygonal habitus.
Holotype: Specimen Sl-1108(K8)15/3 {Plate. 18, Figs. 1-4, 13).
Locus typicus: Tongrube Wittelshofen.
Stratum typicum: Toarcian, ltvesquei and (?) aalensis zone
Description:
Vesicle/plate arrangement of the dinoflagellate Amphiesma cop, pop, cap, 3', 3a, 6", 7c, 6'', 2'"', as, FM, ls, rs, ps; l' insert; tegulation 4', 3'', 4''', 2'''', 7c, 4+, 4++, 3+++; growth of thecal plates in a gonyaulocoid fashion;
Zygote cyst habitus proximate, acavate to cornucavate, somewhat elongated polyhedral, tentoriate epicyst with a very low, pyramidal apical horn and tentoriate hypocyst of equal size, circular in equatorial section; wall composed of a thin pedium and a granulo-prismatically structured luxuria that fuses distally to form the tegillum, surface scabrate, finely chagrinate; without calyptra; finis a!s" tegillum folded into flat carinae, which, as prominent edges, delimit the adjoining flat areas;
Arranging scheme XPR/cop, pop, cap, 3', 3a, 6", 7c, 6"', 2" 11, Xs/as, FM, ps; PR undifferentiated or cop tiny, forming the tip of the apical protuberance and surrounded by pop, area cap small; 3 apicals: IV-nE 1'(V), VI-nE 2'(L), VI-nE 3'(R); 3 anterior intercalaries: caroidale 1a (LDL), fastigiate 2a (D), caroidale 3a (DR); 6 precingulates: anterior geniculate V-nE 1" (WL), anterior geniculate V-nE 2" (LVL), anterior geniculate V-nE 3" (DL), anterior geniculate V-nE 4" (DR), anterior geniculate V-nE 5" (R VR), anterior geniculate V-nE 6" (WR); Cingulum left-handed spiral, indented, heptapartite from lati 1c to 6c and isofastigiate 7c: 6 Postcingulate: posterior linear V-nE 1'" WVL), posterior linear IV-nE 2''' (VL), posterior geniculate V-nE 3"' (LDL), posterior linear IV-nE 4"' (D), posterior linear IV-nE 5'11 (RDR), posterior linear V•nE 6'11 (VR); 2 antapics: V 1"" sloping towards VL, VI 2"" pole-like, slightly inclined towards R; sulcus slightly indented: partit or as and ps against unarticulated central sulcus nonfinat; archaeopyle anteriorly intercalary, la + 2a + 3a; operculum solvat, opercular plates secat, general opercular formula las + 2as + 3a5.
Measure of the holotype:
Length 58 µm, Width 46 µm, thickness 46 µm.
Evansia polyedrica Below, 1990, p.76,78, pl.18, figs.1–4,13; text-figs.22a–e. Holotype: Below, 1990, pl.18, figs.1–4,13. Contrary to the opinion of Lentin and Williams (1993, p.215), this name is validly published. Below (1987a, p.6) stated that, unless otherwise indicated, all the material is in his personal collection. Since Below (1987a, 1987b, 1990) are parts I to III of a single study, we agree with J. Jansonius (personal communication) that Below's (1987a) repository statement refers to all three publications, fulfilling the requirement of ICN Article 40.7. Age: late Toarcian.
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Original description Below, 1990:
Derivatio nominis: named after the polygonal habitus.
Holotype: Specimen Sl-1108(K8)15/3 {Plate. 18, Figs. 1-4, 13).
Locus typicus: Tongrube Wittelshofen.
Stratum typicum: Toarcian, ltvesquei and (?) aalensis zone
Description:
Vesicle/plate arrangement of the dinoflagellate Amphiesma cop, pop, cap, 3', 3a, 6", 7c, 6'', 2'"', as, FM, ls, rs, ps; l' insert; tegulation 4', 3'', 4''', 2'''', 7c, 4+, 4++, 3+++; growth of thecal plates in a gonyaulocoid fashion;
Zygote cyst habitus proximate, acavate to cornucavate, somewhat elongated polyhedral, tentoriate epicyst with a very low, pyramidal apical horn and tentoriate hypocyst of equal size, circular in equatorial section; wall composed of a thin pedium and a granulo-prismatically structured luxuria that fuses distally to form the tegillum, surface scabrate, finely chagrinate; without calyptra; finis a!s" tegillum folded into flat carinae, which, as prominent edges, delimit the adjoining flat areas;
Arranging scheme XPR/cop, pop, cap, 3', 3a, 6", 7c, 6"', 2" 11, Xs/as, FM, ps; PR undifferentiated or cop tiny, forming the tip of the apical protuberance and surrounded by pop, area cap small; 3 apicals: IV-nE 1'(V), VI-nE 2'(L), VI-nE 3'(R); 3 anterior intercalaries: caroidale 1a (LDL), fastigiate 2a (D), caroidale 3a (DR); 6 precingulates: anterior geniculate V-nE 1" (WL), anterior geniculate V-nE 2" (LVL), anterior geniculate V-nE 3" (DL), anterior geniculate V-nE 4" (DR), anterior geniculate V-nE 5" (R VR), anterior geniculate V-nE 6" (WR); Cingulum left-handed spiral, indented, heptapartite from lati 1c to 6c and isofastigiate 7c: 6 Postcingulate: posterior linear V-nE 1'" WVL), posterior linear IV-nE 2''' (VL), posterior geniculate V-nE 3"' (LDL), posterior linear IV-nE 4"' (D), posterior linear IV-nE 5'11 (RDR), posterior linear V•nE 6'11 (VR); 2 antapics: V 1"" sloping towards VL, VI 2"" pole-like, slightly inclined towards R; sulcus slightly indented: partit or as and ps against unarticulated central sulcus nonfinat; archaeopyle anteriorly intercalary, la + 2a + 3a; operculum solvat, opercular plates secat, general opercular formula las + 2as + 3a5.
Measure of the holotype:
Length 58 µm, Width 46 µm, thickness 46 µm.