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Isabelidinium glabrum
Isabelidinium glabrum (Cookson and Eisenack, 1969) Lentin and Williams, 1977
Originally Deflandrea, subsequently Isabelia (combination illegitimate), thirdly (and now) Isabelidinium.
Holotype: Cookson and Eisenack, 1969, fig.1A
Age: Albian-Cenomanian
Occurrence : Balticatta Bore No. 1, between 220-227 feet, and 240 feet, Bore No. 2 at 220 feet.
Description: Shell considerably longer than broad with convex sides that slant towards both apex and antapex. The apex end in a short and bluntly pointed horn; the antapex is truncate or slightly concave with sharply pointed horn on one side. There is no indication of tabulation, girdle or longitudinal furrow. Both the outer wall and that of the capsule are thin and smooth. The capsule is spherical in outline and does not extend to the lateral walls. The archeopyle is relatively large, trapezoidal with rounded corners.
Dimensions: Holotype-length 95 µ, width 52 µ. Range-length about 95-142 µ, width about 52-82 µ.
Comments: The shape of D. glabra is close to that of D. belfastensis Cookson and Eisenack 1961 from an Upper Cretaceous deposit in the Belfast North Bore in S.W. Victoria, between 4645 and 4652 feet. However, the wall of D. belfastensis is prominently granular, whereas that of D. glabra is smooth.
Originally Deflandrea, subsequently Isabelia (combination illegitimate), thirdly (and now) Isabelidinium.
Holotype: Cookson and Eisenack, 1969, fig.1A
Age: Albian-Cenomanian
Occurrence : Balticatta Bore No. 1, between 220-227 feet, and 240 feet, Bore No. 2 at 220 feet.
Description: Shell considerably longer than broad with convex sides that slant towards both apex and antapex. The apex end in a short and bluntly pointed horn; the antapex is truncate or slightly concave with sharply pointed horn on one side. There is no indication of tabulation, girdle or longitudinal furrow. Both the outer wall and that of the capsule are thin and smooth. The capsule is spherical in outline and does not extend to the lateral walls. The archeopyle is relatively large, trapezoidal with rounded corners.
Dimensions: Holotype-length 95 µ, width 52 µ. Range-length about 95-142 µ, width about 52-82 µ.
Comments: The shape of D. glabra is close to that of D. belfastensis Cookson and Eisenack 1961 from an Upper Cretaceous deposit in the Belfast North Bore in S.W. Victoria, between 4645 and 4652 feet. However, the wall of D. belfastensis is prominently granular, whereas that of D. glabra is smooth.