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Valvaeodinium armatum ssp. exile
From Fensome et al., 2019:
Valvaeodinium armatum subsp. exile (Below, 1987b, p.67–69, pl.20, figs.1–5) Lentin and Williams, 1989, p.379.
Holotype: Below, 1987b, pl.20, figs.1–4; Fensome et al., 1993a, fig.3 — p.935.
Originally Valvaeodinium armatum var. exile, subsequently (and now) Valvaeodinium armatum subsp. exile.
Locus typicus: Delme, Lorraine, France
Stratum typicum: Toarcian
Translation Below, 1987: Bureau of Translation, Secretary of State Canada, 1988, Part II, p. 189-190
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Original description: Below, 1987, p. 67-69: Valvaeodinium armatum var. exilis
Diagnosis: A variation of Valvaeodinium armatum; cyst habit proximochorate, acavate, ovaloidal with slightly acuminate apex and rounded antapex, epicyst and hypocyst of equal size, wall composed of firm pedium and microlanate lyxuria which also forms a few, preferentially peniareate, seldom intraareate, appendages measuring 1/4 to 1/5 of the diameter of the cyst; appendages solid, thin cylindrical, distally capitate, cauliforate; the peniareate arrangement of the appendages, and also the limbi reveal the areation formula PR, 4", 1a, 5"", Xc, 5""", 1"""", Xs; archeopyle apical/anterior intercalary, 3" + 1a; operculum solvate, secate, general opercular formula 3"s + 1as.
Dimensions of holotype: Length 37 µm, breadth 32 µm, thickness 32 µm.
Affinities:
Below, 1987, p. 69
Remarks: This taxon is differentiated from the typical Valvaeodinium armatum by a distinctly lesser number of spines. Also, the ends of the spines are not as broadly polyfurcate, but only just thickened or bifid and trifid. In sample 2077 -the only occurrence of this variant so far- this variant forms an evidently morphologically invariable population; i.e., it is not linked with Valvaeodinium armatum var. armatum by morpologically different intermediate forms.
Valvaeodinium armatum subsp. exile (Below, 1987b, p.67–69, pl.20, figs.1–5) Lentin and Williams, 1989, p.379.
Holotype: Below, 1987b, pl.20, figs.1–4; Fensome et al., 1993a, fig.3 — p.935.
Originally Valvaeodinium armatum var. exile, subsequently (and now) Valvaeodinium armatum subsp. exile.
Locus typicus: Delme, Lorraine, France
Stratum typicum: Toarcian
Translation Below, 1987: Bureau of Translation, Secretary of State Canada, 1988, Part II, p. 189-190
---------------------------------------------------------------------------------------------------
Original description: Below, 1987, p. 67-69: Valvaeodinium armatum var. exilis
Diagnosis: A variation of Valvaeodinium armatum; cyst habit proximochorate, acavate, ovaloidal with slightly acuminate apex and rounded antapex, epicyst and hypocyst of equal size, wall composed of firm pedium and microlanate lyxuria which also forms a few, preferentially peniareate, seldom intraareate, appendages measuring 1/4 to 1/5 of the diameter of the cyst; appendages solid, thin cylindrical, distally capitate, cauliforate; the peniareate arrangement of the appendages, and also the limbi reveal the areation formula PR, 4", 1a, 5"", Xc, 5""", 1"""", Xs; archeopyle apical/anterior intercalary, 3" + 1a; operculum solvate, secate, general opercular formula 3"s + 1as.
Dimensions of holotype: Length 37 µm, breadth 32 µm, thickness 32 µm.
Affinities:
Below, 1987, p. 69
Remarks: This taxon is differentiated from the typical Valvaeodinium armatum by a distinctly lesser number of spines. Also, the ends of the spines are not as broadly polyfurcate, but only just thickened or bifid and trifid. In sample 2077 -the only occurrence of this variant so far- this variant forms an evidently morphologically invariable population; i.e., it is not linked with Valvaeodinium armatum var. armatum by morpologically different intermediate forms.