Cepadinium DUXBURY 1983

Original diagnosis:

"Proximo-cavate, peridiniacean dinoflagellate cysts which are dorso-ventrally flattened with a slight ventral concavity. Three horns are usually present, consisting of one apical, one well-developed left-antapical and one reduced right-antapical. Three or four body layers are usually present, in which case an ornament of granules and/or coni may be present on the second layer in. As few as two layers may be seen and in this case, the granules and/or coni are present on the external surface. A laevo-rotatory paracingulum is present, and, laterally, a paracingular notch may be observed which becomes increasingly pronounced with an increasing number of body layers. The archeopyle is of a 3A2'-4'3I type and the operculum usually remains attached ventrally." - From Duxbury (1983, p. 58).

Cepadinium variabilis DUXBURY 1983

Pl. 9, fig(s). 4
NHM registration number: FD58(2)

Transmitted light images:

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Ventral face in high focus
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Optical section
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Dorsal face in low focus

CLSM stills:

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Maximum Projection
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Shadow Projection
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Red/Green Anaglyph

Original diagnosis:

"A proximo-cavate dinoflagellate cyst possessing well-developed apical and left-antapical horns and a right-antapical horn which is reduced to varying degrees. Four body layers are present in the most completely preserved specimens but more commonly only three are observed. In each of these cases, a granular and/or conical body ornament is present on the second layer in. Two body layers may be observed in extreme cases, in which event the ornament is observed on the outer layer. A laevorotatory paracingulum is always present, as is a ventral depression which may contain a poorly-defined rostrum. The archeopyle is of a 3A2'-4'3I type and the operculum usually remains attached ventrally. No paratabulation other that that reflected by the paracingulum and archeopyle margin has been observed." - From Duxbury (1983, p. 58).


According to Lister & Batten (1988b, p.43), this species is a taxonomic junior synonym of Deflandrea ventriosa Alberti 1959b [Now = Cepadinium ventriosum (Alberti 1959b) Lentin & Williams 1989].

The holotype of Cepadinium variabile remains the nomenclatural type of the genus Cepadinium Duxbury 1983.

The correct spelling of the species name is Cepadinium variabile, since the adjectival specific epithet must agree grammatically with the generic name, which is neuter.

(See Williams et al., 1998).