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Impagidinium maculatum
Impagidinium maculatum (Cookson and Eisenack, 1961) Stover and Evitt, 1978
Originally Leptodinium, subsequently (and now) Impagidinium.
Holotype: Cookson and Eisenack 1961: Plate II, Figs. 5, 6
Locus typicus: Rottnest Island Bore, Western Australia
Stratum typicum: Lower Tertiary
Age: Eocene
Description: Cookson and Eisenack 1961, p. 40: Leptodinium maculatum
Shell oval to nearly spherical, without a horn. Girdle equatorial, strongly helicoid and rather broad with low borders. Longitudinal furrow broad, elongate-rectangular, bounded antapically by a large plate. Plates strongly outlined, bordered by low, thin, hyaline ledges. Surface of the plates distinctly dotted. Pylome formed by removal of plate 3"". Tabulation 4", 6"", 5""", 1 p, 1"""".
Dimensions: Type 52µ long; 50µ broad. Range: Length 52-64µ, breadth 48-60µ.
Comments: L. maculatum is close to the Upper Oligocene species L. membranigerum Gerlach 1961 from north-western Germany. However the latter can be distinguished from the Rottnest species by its more elongated egg-shaped form, the higher ledges and the finely granular surface of the plates.
Originally Leptodinium, subsequently (and now) Impagidinium.
Holotype: Cookson and Eisenack 1961: Plate II, Figs. 5, 6
Locus typicus: Rottnest Island Bore, Western Australia
Stratum typicum: Lower Tertiary
Age: Eocene
Description: Cookson and Eisenack 1961, p. 40: Leptodinium maculatum
Shell oval to nearly spherical, without a horn. Girdle equatorial, strongly helicoid and rather broad with low borders. Longitudinal furrow broad, elongate-rectangular, bounded antapically by a large plate. Plates strongly outlined, bordered by low, thin, hyaline ledges. Surface of the plates distinctly dotted. Pylome formed by removal of plate 3"". Tabulation 4", 6"", 5""", 1 p, 1"""".
Dimensions: Type 52µ long; 50µ broad. Range: Length 52-64µ, breadth 48-60µ.
Comments: L. maculatum is close to the Upper Oligocene species L. membranigerum Gerlach 1961 from north-western Germany. However the latter can be distinguished from the Rottnest species by its more elongated egg-shaped form, the higher ledges and the finely granular surface of the plates.