Back
Dioxya rotunda
Dioxya rotunda (Wilson, 1967) Morgan, 1977
Now Vozzhennikovia. Originally Spinidinium, subsequently (and now) Vozzhennikovia, thirdly Dioxya.
Lentin and Williams, 1981, retained this species in Vozzhennikovia Lentin and Williams, 1976.
Holotype: Wilson, 1967, fig.6
Locus typicus: Erratics on Black Island, McMurdo Sound, Antarctica
Stratum typicum: Eocene
Original diagnosis: Wilson, 1967, p.64: Spinidinium rotundum
Shell circular or near-circular, single-layered; surface covered with numerous small spines. Apical horn relatively large (L=8-11 µm) rectangular; right antapical horn small, Pointed (L=4-5 Ám); left antapical horn absent. Transverse girdle faintly defined by a double row of spine-bearing ridges which are usually discontinuous. Wide longitudinal furrow. Intercalary archeopyle wide, hexagonal, located on dorsal epitheca; operculum free. Atabulate.
Dimensions: Holotype: L=65 µm, b=58 µm. Range: L=55(66)72 µm, b=47(52)58 µm.
Now Vozzhennikovia. Originally Spinidinium, subsequently (and now) Vozzhennikovia, thirdly Dioxya.
Lentin and Williams, 1981, retained this species in Vozzhennikovia Lentin and Williams, 1976.
Holotype: Wilson, 1967, fig.6
Locus typicus: Erratics on Black Island, McMurdo Sound, Antarctica
Stratum typicum: Eocene
Original diagnosis: Wilson, 1967, p.64: Spinidinium rotundum
Shell circular or near-circular, single-layered; surface covered with numerous small spines. Apical horn relatively large (L=8-11 µm) rectangular; right antapical horn small, Pointed (L=4-5 Ám); left antapical horn absent. Transverse girdle faintly defined by a double row of spine-bearing ridges which are usually discontinuous. Wide longitudinal furrow. Intercalary archeopyle wide, hexagonal, located on dorsal epitheca; operculum free. Atabulate.
Dimensions: Holotype: L=65 µm, b=58 µm. Range: L=55(66)72 µm, b=47(52)58 µm.