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Wetzeliella (Apectodinium) hyperacantha
Wetzeliella (Apectodinium) hypercantha (Cookson and Eisenack, 1965) Lentin and Williams, 1977
Originally Wetzeliella subgenus Apectodinium, subsequently (and now) Apectodinium.
Holotype: Cookson and Eisenack, 1965, pl.16, fig.5
Locus typicus: Dartmoor Formation, SW Victoria, Australia
Stratum typicum: Palaeocene
Original description: Cookson and Eisenack, 1965, p. 134-135: Wetzeliella hypercantha
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 appandages, 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 appandages 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 appandages 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:
Cookson and Eisenack, 1965, p. 135: Wetzeliella hypercantha
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 ist consistantly smaller size, the greater prominence of the lateral horns, the smaller and more numerous appandages, and the shape of the archaeopyle.
Originally Wetzeliella subgenus Apectodinium, subsequently (and now) Apectodinium.
Holotype: Cookson and Eisenack, 1965, pl.16, fig.5
Locus typicus: Dartmoor Formation, SW Victoria, Australia
Stratum typicum: Palaeocene
Original description: Cookson and Eisenack, 1965, p. 134-135: Wetzeliella hypercantha
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 appandages, 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 appandages 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 appandages 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:
Cookson and Eisenack, 1965, p. 135: Wetzeliella hypercantha
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 ist consistantly smaller size, the greater prominence of the lateral horns, the smaller and more numerous appandages, and the shape of the archaeopyle.