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Heterosphaeridium heteracanthum ssp. heteracanthum
From Fensome et al., 2019:
Heterosphaeridium heteracanthum ssp. heteracanthum Autonym. Holotype: Deflandre and Cookson, 1955, pl.2, fig.5; Fauconnier and Masure, 2004, pl.35, figs.7–8. Originally Hystrichosphaeridium heteracanthum subsp. heteracanthum, subsequently (and now) Heterosphaeridium heteracanthum subsp. heteracanthum, thirdly Heterosphaeridium? heteracanthum subsp. heteracanthum.
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Locus typicus: Victoria, Australia
Stratum typicum: ?Palaeocene-Lower Eocene
Original description: Deflandre and Cookson, 1955, p. 276: Hystrichosphaeridium heteracanthum
Shell large, approximately circular in outline, with numerous appandages of variable size, shape and form. Appandages solid, usually elongated, frequently filiform, sometimes as beoad as long, the apices either pointed, everted, or irregulary branched. Surface of shell punctate.
Dimensions: Shell 56-107 µm, appendages 5-36 µm long (majority between 13 and 23 µm).
Emended diagnosis: Radmacher et al., 2013, p.33, 36: (based on original description and photograph of Deflandre and Cookson, 1955, pl. 2, figs. 5, 6): Large, gonyaulacacean, circular in outline, chorate to proximo-chorate cyst with an apical archaeopyle. Numerous, non-tabular processes are characterised by variable shape, length and width. All processes are solid, usually elongated and their endings differ significantly. They may be pointed, everted or irregularly branched, never “scythe-like” or distally connected. Wall structure is punctate.
Heterosphaeridium heteracanthum ssp. heteracanthum Autonym. Holotype: Deflandre and Cookson, 1955, pl.2, fig.5; Fauconnier and Masure, 2004, pl.35, figs.7–8. Originally Hystrichosphaeridium heteracanthum subsp. heteracanthum, subsequently (and now) Heterosphaeridium heteracanthum subsp. heteracanthum, thirdly Heterosphaeridium? heteracanthum subsp. heteracanthum.
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Locus typicus: Victoria, Australia
Stratum typicum: ?Palaeocene-Lower Eocene
Original description: Deflandre and Cookson, 1955, p. 276: Hystrichosphaeridium heteracanthum
Shell large, approximately circular in outline, with numerous appandages of variable size, shape and form. Appandages solid, usually elongated, frequently filiform, sometimes as beoad as long, the apices either pointed, everted, or irregulary branched. Surface of shell punctate.
Dimensions: Shell 56-107 µm, appendages 5-36 µm long (majority between 13 and 23 µm).
Emended diagnosis: Radmacher et al., 2013, p.33, 36: (based on original description and photograph of Deflandre and Cookson, 1955, pl. 2, figs. 5, 6): Large, gonyaulacacean, circular in outline, chorate to proximo-chorate cyst with an apical archaeopyle. Numerous, non-tabular processes are characterised by variable shape, length and width. All processes are solid, usually elongated and their endings differ significantly. They may be pointed, everted or irregularly branched, never “scythe-like” or distally connected. Wall structure is punctate.