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Isabelia madurensis
Isabelia madurensis (Cookson and Eisenack, 1970) Lentin and Williams, 1976
Combination illegitimate since the generic name Isabelia is illegitimate.
Now Eucladinium. Originally Deflandrea, subsequently Isabelia (combination illegitimate), thirdly Isabelidinium, fourthly (and now) Eucladinium.
Holotype: Cookson and Eisenack, 1970, pl.11, fig.3
Age: Senonian
Original description: Cookson and Eisenack, 1970, p.140
Shell longer than broad, epitheca somcwhat larger than hypotheca with outwardly slanting sides and a small apical horn. The sides of the hypotheca slant towards a very small antapical horn which is situated on the lefthand side of the antapex. A large circular internal capsule almost fills the hypotheca and extends to nearly half way up the epitheca.
The archeopyle is intercalary, relativcly large and rounded in outlinc with a straight base. The wall of the epitheca is typically completely and closely covercd with small dot-like thickenings. A girdle has been clearly evident on the ventral surface of the paratype (Pl. 11, fig. 4).
Dimensions: Holotype: c. 90 Ám long, 72 Ám broad. Range of 10 specimens: c. 74-96 Ám long, 60-84 Ám broad.
Affinities:
Cookson and Eisenack, 1970, p.140: D. madurensis is obviously very closely related D. gambangensis. However, the main distinguishing characters, namely the more complete filling of the hypotheca by the internal capsule, the smaller size and different shape of the antapical projection, and the more complete and denser arrangement of the surfacc thickenings, have been so constant in their occurrence that, for the present at least, the specific separation of these two forms, adopted herein, seems justified.
Combination illegitimate since the generic name Isabelia is illegitimate.
Now Eucladinium. Originally Deflandrea, subsequently Isabelia (combination illegitimate), thirdly Isabelidinium, fourthly (and now) Eucladinium.
Holotype: Cookson and Eisenack, 1970, pl.11, fig.3
Age: Senonian
Original description: Cookson and Eisenack, 1970, p.140
Shell longer than broad, epitheca somcwhat larger than hypotheca with outwardly slanting sides and a small apical horn. The sides of the hypotheca slant towards a very small antapical horn which is situated on the lefthand side of the antapex. A large circular internal capsule almost fills the hypotheca and extends to nearly half way up the epitheca.
The archeopyle is intercalary, relativcly large and rounded in outlinc with a straight base. The wall of the epitheca is typically completely and closely covercd with small dot-like thickenings. A girdle has been clearly evident on the ventral surface of the paratype (Pl. 11, fig. 4).
Dimensions: Holotype: c. 90 Ám long, 72 Ám broad. Range of 10 specimens: c. 74-96 Ám long, 60-84 Ám broad.
Affinities:
Cookson and Eisenack, 1970, p.140: D. madurensis is obviously very closely related D. gambangensis. However, the main distinguishing characters, namely the more complete filling of the hypotheca by the internal capsule, the smaller size and different shape of the antapical projection, and the more complete and denser arrangement of the surfacc thickenings, have been so constant in their occurrence that, for the present at least, the specific separation of these two forms, adopted herein, seems justified.