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Alterbia acribes
Alterbia acribes, (Davey and Verdier, 1971), Lentin and Williams, 1976
NOW Angustidinium. Originally Deflandrea, subsequently Alterbia (combination illegitimate), thirdly (and now) Angustidinium, fourthly Moesiodinium. Stover and Evitt, 1978, considered this to be a problematical species of Alterbia
Holotype: Davey and Verdier, 1971, pl.2, fig.10
Locus typicus: Cotes Noires de Moeslains, northeastern France
Stratum typicum: Leymeriella tardefurcata Zone, Early Albian
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Original description as Deflandrea acribes: [Davey and Verdier, 1971, p. 38-39]:
Diagnosis:
Small spherical cyst possessing thin outer wall surrounding moderately thick walled inner body. Outer wall forms an angular apical horn and two rounded antapical horns. Low ridges on this membrane define a broad cingulum and a ventral furrow. Weak tabulation usually shown by aligned granules. Intercalary archaeopyle sometimes apparent.
Description:
The apical horn is of a characteristic shape, in that there are lateral extensions onto the intercalary area. In one specimen an intercalary archaeopyle (Type I, Evitt, 1967) appeared to be present. However, as a Peridinoid-tabulation may be apparent, it is often possible to observe the intercalary plate 2a in situ. It is probable that this plate is hinged and returned into position after excystment took place. This species was not seen to be stained by safranin.
NOW Angustidinium. Originally Deflandrea, subsequently Alterbia (combination illegitimate), thirdly (and now) Angustidinium, fourthly Moesiodinium. Stover and Evitt, 1978, considered this to be a problematical species of Alterbia
Holotype: Davey and Verdier, 1971, pl.2, fig.10
Locus typicus: Cotes Noires de Moeslains, northeastern France
Stratum typicum: Leymeriella tardefurcata Zone, Early Albian
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description as Deflandrea acribes: [Davey and Verdier, 1971, p. 38-39]:
Diagnosis:
Small spherical cyst possessing thin outer wall surrounding moderately thick walled inner body. Outer wall forms an angular apical horn and two rounded antapical horns. Low ridges on this membrane define a broad cingulum and a ventral furrow. Weak tabulation usually shown by aligned granules. Intercalary archaeopyle sometimes apparent.
Description:
The apical horn is of a characteristic shape, in that there are lateral extensions onto the intercalary area. In one specimen an intercalary archaeopyle (Type I, Evitt, 1967) appeared to be present. However, as a Peridinoid-tabulation may be apparent, it is often possible to observe the intercalary plate 2a in situ. It is probable that this plate is hinged and returned into position after excystment took place. This species was not seen to be stained by safranin.