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Apectodinium hyperacanthum
From Fensome et al., 2019:
Apectodinium hypercanthum, (Cookson and Eisenack, 1965b, p.134–135, pl.16, figs.3–6) Lentin and Williams, 1977b, p.8.
Holotype: Cookson and Eisenack, 1965b, pl.16, fig.5.
Originally Wetzeliella, subsequently Wetzeliella subgenus Apectodinium, thirdly (and now) Apectodinium.
Costa and Downie (1976, p.609) assigned this species to Wetzeliella subgenus Apectodinium.
Age: Paleocene.
Locus typicus: Dartmoor Formation, SW Victoria, Australia
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Original description as Wetzeliella hypercantha: [Cookson and Eisenack, 1965, p. 134-135]:
Description:
Shell flat with approximately straight to convex sides and well-developed apical, antapical and lateral projections or horns, the lateral being the most conspicuous. The wall of the shell thin and well-covered with simple or occasionally branched appendages, the apices of which are bluntly pointed, capitate or slightly bifurcate. The apical horn is short and blunt with 2 or 3 divergent, branched or unbranched appendages at its apex. The antapical horn varies in length but, as in the holotype, is usually long and narrowed to a blunt tip. The lateral horns are covered with appendages similar to those on the general surface. The capsule is circular to oval in outline and practically fills the shell. The archaeopyle, which develops just below the apex, is small and rounded to slightly angular in outline.
Dimensions:
Holotype: 110 µm long, 110 µm broad; capsule 69x64 µm.
Range - 80-100 µm long, 85-110 µm broad; capsule 50-69 µm long, 56-69 µm broad.
Affinities:
Of the previously described species of Wetziella, W. hypercantha approaches most closely W. symmetrica Weiler (1956). The main features which distinguish it from this species are consistently smaller size, the greater prominence of the lateral horns, the smaller and more numerous appendages, and the shape of the archaeopyle.
Apectodinium hypercanthum, (Cookson and Eisenack, 1965b, p.134–135, pl.16, figs.3–6) Lentin and Williams, 1977b, p.8.
Holotype: Cookson and Eisenack, 1965b, pl.16, fig.5.
Originally Wetzeliella, subsequently Wetzeliella subgenus Apectodinium, thirdly (and now) Apectodinium.
Costa and Downie (1976, p.609) assigned this species to Wetzeliella subgenus Apectodinium.
Age: Paleocene.
Locus typicus: Dartmoor Formation, SW Victoria, Australia
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Original description as Wetzeliella hypercantha: [Cookson and Eisenack, 1965, p. 134-135]:
Description:
Shell flat with approximately straight to convex sides and well-developed apical, antapical and lateral projections or horns, the lateral being the most conspicuous. The wall of the shell thin and well-covered with simple or occasionally branched appendages, the apices of which are bluntly pointed, capitate or slightly bifurcate. The apical horn is short and blunt with 2 or 3 divergent, branched or unbranched appendages at its apex. The antapical horn varies in length but, as in the holotype, is usually long and narrowed to a blunt tip. The lateral horns are covered with appendages similar to those on the general surface. The capsule is circular to oval in outline and practically fills the shell. The archaeopyle, which develops just below the apex, is small and rounded to slightly angular in outline.
Dimensions:
Holotype: 110 µm long, 110 µm broad; capsule 69x64 µm.
Range - 80-100 µm long, 85-110 µm broad; capsule 50-69 µm long, 56-69 µm broad.
Affinities:
Of the previously described species of Wetziella, W. hypercantha approaches most closely W. symmetrica Weiler (1956). The main features which distinguish it from this species are consistently smaller size, the greater prominence of the lateral horns, the smaller and more numerous appendages, and the shape of the archaeopyle.