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Ovoidinium torulosum
Ovoidinium? torulosum (Davey and Verdier, 1973) Below, 1981
Now Canningia. Originally (and now) Canningia, subsequently Batiacasphaera, thirdly Ovoidinium.
Lentin and Williams, 1985, retained this species in Canningia Cookson and Eisenack, 1960.
Holotype: Davey and Verdier, 1973, pl.1, fig.2
Age: Late Albian-Early Cenomanian
Original diagnosis: Davey and Verdier 1973, p. 180: Canningia torulosa
The cyst is dorso-ventrally flattened, subcircular to ovoidal in outline and without apical or antapical structures. The wall is thin, smooth to lightly granular, and bears a number of low tubercles of circular outline. They are irregularly aligned along the plate margins and are especially noticeable along the borders of the cingulum; intratabular tubercles are also present. The cingulum, which divides the cyst into an epitract and hypotract of equal size, and sulcus are usually devoid of ornamentation. An apical archaeopyle is present with the operculum often remaining in place. The former is only slightly angular and precingular sutural breakages are rarely present.
Dimensions HolotypeParatypeRange
Cyst length ......... 59 µ 52 (56) 61µ
Cyst length (with archaeopyle) 41 µ 41-58 µ
Cyst width ......... 51 µ 45 µ 45 (51) 65 µ
Original description: Davey and Verdier 1973, p. 180: Canningia torulosa
Since the cyst wall is relatively thin (approximately 1 ll) and the cyst originally of subspherical shape, some distortion is always present This distortion most usually takes the form of one or two longitudinal folds (pl. 1, fig. 5). The tubercles are low ( under than 1µ in height ) and disclike, being circular in outline and approximately 1µ in diameter. Tubercle alignment in the pre- and postcingular areas is always very noticeable and presumably follows the reflected plate boundaries. However, these boundaries, except in the case of the cingulum, are never completely outlined and this, together with the presence of intratabular tubercles, makes the cyst tabulation difficult to decipher.
Remarks: C. torulosa sp. nov. is an easily recognisable species and immediatley distinguishable from all previous described forms.
Now Canningia. Originally (and now) Canningia, subsequently Batiacasphaera, thirdly Ovoidinium.
Lentin and Williams, 1985, retained this species in Canningia Cookson and Eisenack, 1960.
Holotype: Davey and Verdier, 1973, pl.1, fig.2
Age: Late Albian-Early Cenomanian
Original diagnosis: Davey and Verdier 1973, p. 180: Canningia torulosa
The cyst is dorso-ventrally flattened, subcircular to ovoidal in outline and without apical or antapical structures. The wall is thin, smooth to lightly granular, and bears a number of low tubercles of circular outline. They are irregularly aligned along the plate margins and are especially noticeable along the borders of the cingulum; intratabular tubercles are also present. The cingulum, which divides the cyst into an epitract and hypotract of equal size, and sulcus are usually devoid of ornamentation. An apical archaeopyle is present with the operculum often remaining in place. The former is only slightly angular and precingular sutural breakages are rarely present.
Dimensions HolotypeParatypeRange
Cyst length ......... 59 µ 52 (56) 61µ
Cyst length (with archaeopyle) 41 µ 41-58 µ
Cyst width ......... 51 µ 45 µ 45 (51) 65 µ
Original description: Davey and Verdier 1973, p. 180: Canningia torulosa
Since the cyst wall is relatively thin (approximately 1 ll) and the cyst originally of subspherical shape, some distortion is always present This distortion most usually takes the form of one or two longitudinal folds (pl. 1, fig. 5). The tubercles are low ( under than 1µ in height ) and disclike, being circular in outline and approximately 1µ in diameter. Tubercle alignment in the pre- and postcingular areas is always very noticeable and presumably follows the reflected plate boundaries. However, these boundaries, except in the case of the cingulum, are never completely outlined and this, together with the presence of intratabular tubercles, makes the cyst tabulation difficult to decipher.
Remarks: C. torulosa sp. nov. is an easily recognisable species and immediatley distinguishable from all previous described forms.