Back
Palaeocystodinium sp. a of costa and downie 1979

Palaeocystodinium sp. A of Costa and Downie 1979
-------------------------------------------------------

Genus: Palaeocystodinium Alberti, 1961
tax. sr. synonym of Cystodiniopsis Vozzhennikova, 1963, according to Vozzhennikova, 1967.
tax. jr. synonym of Svalbardella Manum, 1960, according to Lindgren, 1984. Wrenn and Hart, 1988, retained Palaeocystodinium as a separate genus.
Type species: Palaeocystodinium golzowense Alberti, 1961
Translation Alberti, 1961: Stover and Evitt, 1978, p. 115

Original description: Alberti, 1961, p. 20
Body fusiform, more or less flattened dorsoventrally. With hornlike processes at both ends; these taper towards their free ends. With a rounded-trapezoidal pylome below the apex. Always with a roundish to ellipsoidal inner body closely appressed against the outer shell.
Stover and Evitt, 1978, p 115
Synopsis: Cysts proximate, cornucavate or circumcavate, elongate ellipsoidal, with single slender pointed apical and antapical horns at each pole; paratabulation indicated by archaeopyle only; archaeopyle intercalary, Type I; archaeopyle index generally <0.5.
Modified description: Shape: elongate ellipsoidal; apical and antapical horns pointed and generally significantly narrower than part of cyst containing the endocyst.
Wall relationships: cysts cornucavate or circumcavate; endocyst subspherical to elongate ellipsoidal.
Wall features: No parasutural features. Periphragm smooth to faintly ornamented; scattered spinulae or granulae may be anywhere on periphragm, but tend to be found most frequently at or near ends of horns. Antapical horn may have short lateral spur.
Paratabulation: Indicated by archaeopyle only.
Archaeopyle: Intercalary, Type I (2a only); height greater than width; archaeopyle index generally <0.5; operculum free.
Paracingulum: Generally not indicated.
Parasulcus: Not indicated.
Size: Large.

Affinities:
Stover and Evitt, 1978, p. 115: Palaeocystodinium differs from Svalbardella in having slender pointed apical and antapical horns and in lacking indications of paratabulation other than the archaeopyle.
Feedback/Report bug