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Ascodinium cinctum
Ascodinium cinctum, (Cookson and Eisenack, 1958), Helenes, 1983
NOW Ovoidinium. Originally Deflandrea, subsequently Evittia (combination illegitimate), thirdly Pocockia, fourthly (and now) Ovoidinium, fifthly Ascodinium. Lentin and Williams, 1989, retained this species in Ovoidinium Davey, 1970.
Holotype: Cookson and Eisenack, 1958, pl.4, fig.3
Locus typicus: Birdrong Formation, W Australia
Stratum typicum: Late Neocomian-Early Aptian
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Original description as Deflandrea cincta: [Cookson and Eisenack, 1958, p. 26]:
Description:
Theca elongated, clearly separated into an epitheca and hypotheca by a strongly marked transverse girdle, a short longitudinal furrow is situated on the ventral surface of the hypotheca. The epitheca is convex laterally and narrows rather abruptly towards a short terminal truncated horn with a small central projection. The hypotheca is slightly narrower than the epitheca and posteriorly is prolonged on one side into a short, broad, sharply-pointed horn and on the other into a broadly conical expansion. The external membrane is somewhat coarsely granular. The capsule is smooth, broadly oval, and usually extends laterally to the pouter membrane.
Dimensions:
Type - theca 88 x 52 µm; capsule 55 x 40 µm.
Range - theca 81-118 x 52-66 µm; capsule 52-66 x 45-57 µm.
Affinities:
Deflandrea cincta although differing from the genotype D. phosphoritica Eis. and other species in having a prominent transverse girdle, is, by its shape, absence of plates and in the presence of an internal capsule, clearly a member of the genus Deflandrea.
NOW Ovoidinium. Originally Deflandrea, subsequently Evittia (combination illegitimate), thirdly Pocockia, fourthly (and now) Ovoidinium, fifthly Ascodinium. Lentin and Williams, 1989, retained this species in Ovoidinium Davey, 1970.
Holotype: Cookson and Eisenack, 1958, pl.4, fig.3
Locus typicus: Birdrong Formation, W Australia
Stratum typicum: Late Neocomian-Early Aptian
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Original description as Deflandrea cincta: [Cookson and Eisenack, 1958, p. 26]:
Description:
Theca elongated, clearly separated into an epitheca and hypotheca by a strongly marked transverse girdle, a short longitudinal furrow is situated on the ventral surface of the hypotheca. The epitheca is convex laterally and narrows rather abruptly towards a short terminal truncated horn with a small central projection. The hypotheca is slightly narrower than the epitheca and posteriorly is prolonged on one side into a short, broad, sharply-pointed horn and on the other into a broadly conical expansion. The external membrane is somewhat coarsely granular. The capsule is smooth, broadly oval, and usually extends laterally to the pouter membrane.
Dimensions:
Type - theca 88 x 52 µm; capsule 55 x 40 µm.
Range - theca 81-118 x 52-66 µm; capsule 52-66 x 45-57 µm.
Affinities:
Deflandrea cincta although differing from the genotype D. phosphoritica Eis. and other species in having a prominent transverse girdle, is, by its shape, absence of plates and in the presence of an internal capsule, clearly a member of the genus Deflandrea.