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Manumiella lata
Manumiella lata (Cookson and Eisenack, 1968) Bujak and Davies, 1983
Originally Deflandrea, subsequently Isabelidinium, thirdly (and now) Manumiella. See also Isabelia (combination illegitimate).
Holotype: Cookson and Eisenack 1968: Figure 1a
Locus typicus: Gingin Brook silty limestone at 202-204 feet, Western Australia
Stratum typicum: Upper Cretaceous
Age: ?Santonian-Early Campanian
Description: Cookson and Eisenack 1968: Deflandrea lata
Shell rather flat, without tabulation, broadly oval to nearly circular in outline, without a elearly defined girdle, occasionally a slight marginal indentation suggestive of a girdle has been present (Fig. lA). Apex of shell with a small median and slightly concave prominence; antapex narrower and more deeply concave than the apex with two short antapical horns. Capsule widely separated from the wall of shell, nearly spherical to broadly oval in outline, its longer axis being at right angles to the longitudinal axis of the shell. Areheopyle small, intercalary in position, circular to oval in outline. Wall of both shell and capsule smooth and thin, that of the capsule being the thinner of the two.
Dimensions. Holotype: overall length 98µ, overall width 84 µ, capsule c. 50 x 57 µ. Range: overall length c. 78-105µ, overall width c. 76-97µ; capsule length c. 48-50µ, width c. 48-75µ.
Comment. Of the described species of Deflandrea, D. lata appears to come closest to D. cretacea Cookson 1956 originally described from three Upper Cretaceous deposits in the Nelson Bore, Victoria. It agrees with D. cretacea in the apparent absence of a girdle, but differs from this species in its rounded shape, the complete separation of the capsule from the shell and the greater prominence of the antapical projections .
Originally Deflandrea, subsequently Isabelidinium, thirdly (and now) Manumiella. See also Isabelia (combination illegitimate).
Holotype: Cookson and Eisenack 1968: Figure 1a
Locus typicus: Gingin Brook silty limestone at 202-204 feet, Western Australia
Stratum typicum: Upper Cretaceous
Age: ?Santonian-Early Campanian
Description: Cookson and Eisenack 1968: Deflandrea lata
Shell rather flat, without tabulation, broadly oval to nearly circular in outline, without a elearly defined girdle, occasionally a slight marginal indentation suggestive of a girdle has been present (Fig. lA). Apex of shell with a small median and slightly concave prominence; antapex narrower and more deeply concave than the apex with two short antapical horns. Capsule widely separated from the wall of shell, nearly spherical to broadly oval in outline, its longer axis being at right angles to the longitudinal axis of the shell. Areheopyle small, intercalary in position, circular to oval in outline. Wall of both shell and capsule smooth and thin, that of the capsule being the thinner of the two.
Dimensions. Holotype: overall length 98µ, overall width 84 µ, capsule c. 50 x 57 µ. Range: overall length c. 78-105µ, overall width c. 76-97µ; capsule length c. 48-50µ, width c. 48-75µ.
Comment. Of the described species of Deflandrea, D. lata appears to come closest to D. cretacea Cookson 1956 originally described from three Upper Cretaceous deposits in the Nelson Bore, Victoria. It agrees with D. cretacea in the apparent absence of a girdle, but differs from this species in its rounded shape, the complete separation of the capsule from the shell and the greater prominence of the antapical projections .