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Alisogymnium laeve
From Fensome et al., 2019:
Alisogymnium laeve, (Vozzhennikova, 1967, p.48, pl.1, fig.4; pl.2, fig.5) Lentin and Vozzhennikova, 1990, p.26.
Emendation: Lentin and Vozzhennikova, 1990, p.26–27, as Alisogymnium laeve.
Holotype: Vozzhennikova, 1967, pl.2, fig.5; Lentin and Vozzhennikova, 1990, pl.2, fig.7a; lost according to Lentin and Vozzhennikova (1990, p.26).
Neotype: Harland, 1973, pl.85, figs.2–3 (as Dinogymnium longicornis); Lentin and Vozzhennikova, 1990, pl.2, fig.7b; designated by Lentin and Vozzhennikova (1990, p.27).
Originally Gymnodinium sphaerocephalum var. laeve (Appendix B), subsequently Dinogymnium sphaerocephalum subsp. laeve, thirdly (and now) Alisogymnium laeve.
Age: Senonian.
Locus typicus: Western Siberia (R. Vakh), USSR
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Original description as Gymnodinium sphaerocephalum var. laeve: [Vozzhennikova, 1967, p. 48]:
Description:
Epitheca hemispherical, separated from the hypotheca by a deep furrow. Hypotheca funnelshaped and ribbed, the surface of the epitheca being smooth.
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Emended description: [Lentin and Vozzhennikova, 1990 p. 27]:
Description:
Cysts shape roundly elongate; epicyst conical to mildly funnel-shaped; hypocyst short, broadly rounded; autophragm microporate, epicyst with delicate longitudinal ridges more or less developed, hypocyst without ridges; archeopyle formed by two short arcuate sutures, which results in the loss of a single apical paraplate: paracingulum deep, dividing the cyst into two unequal portions, the epicyst being longer; parasulcus indistinct, indicated by a shallow longitudinal depression in the slightly off-set paracingulum.
Dimensions/Size:
Neotype: length 42 µm, width 32 µm, width of paracingulum 4 µm.
Range: 39-59 µm in length and 19-33 µm in width.
Alisogymnium laeve, (Vozzhennikova, 1967, p.48, pl.1, fig.4; pl.2, fig.5) Lentin and Vozzhennikova, 1990, p.26.
Emendation: Lentin and Vozzhennikova, 1990, p.26–27, as Alisogymnium laeve.
Holotype: Vozzhennikova, 1967, pl.2, fig.5; Lentin and Vozzhennikova, 1990, pl.2, fig.7a; lost according to Lentin and Vozzhennikova (1990, p.26).
Neotype: Harland, 1973, pl.85, figs.2–3 (as Dinogymnium longicornis); Lentin and Vozzhennikova, 1990, pl.2, fig.7b; designated by Lentin and Vozzhennikova (1990, p.27).
Originally Gymnodinium sphaerocephalum var. laeve (Appendix B), subsequently Dinogymnium sphaerocephalum subsp. laeve, thirdly (and now) Alisogymnium laeve.
Age: Senonian.
Locus typicus: Western Siberia (R. Vakh), USSR
---------------------------------------------------------------------------------------------------
Original description as Gymnodinium sphaerocephalum var. laeve: [Vozzhennikova, 1967, p. 48]:
Description:
Epitheca hemispherical, separated from the hypotheca by a deep furrow. Hypotheca funnelshaped and ribbed, the surface of the epitheca being smooth.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Emended description: [Lentin and Vozzhennikova, 1990 p. 27]:
Description:
Cysts shape roundly elongate; epicyst conical to mildly funnel-shaped; hypocyst short, broadly rounded; autophragm microporate, epicyst with delicate longitudinal ridges more or less developed, hypocyst without ridges; archeopyle formed by two short arcuate sutures, which results in the loss of a single apical paraplate: paracingulum deep, dividing the cyst into two unequal portions, the epicyst being longer; parasulcus indistinct, indicated by a shallow longitudinal depression in the slightly off-set paracingulum.
Dimensions/Size:
Neotype: length 42 µm, width 32 µm, width of paracingulum 4 µm.
Range: 39-59 µm in length and 19-33 µm in width.