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Lithodinia jurassica var. ornata
Lithodinia jurassica var. ornata Eisenack, 1935, p.176, pl.4, figs.9-10; text-figs.1-4.
NOW Ctenidodinium ornatum. Originally Lithodinia jurassica var. ornata, subsequently (and now) Ctenidodinium ornatum, thirdly Gonyaulacysta ornata. Taxonomic junior synonym: Brotzenia (as Ctenidodinium?) cristata, according to Woollam (1983, p.190).
Holotype: Eisenack, 1935, pl.4, fig.9.
Age: Oxfordian. Parent: Lithodinia jurassica
Translations Eisenack, 1935: LPP
Original description: Eisenack 1935, p.175-176
Annotated description: Body mostly polyhedral and in dorsal or ventral view a slightly elongate hexagon with more or less convex sides; occasionally spherical. Hypocyst as large as or slightly higher than epicyst. Cingulum clear, but quite flat. Sulcus hardly discernible, apparently extremely flat. In equatorial section ring-shaped. Equatorial plates (pre- and postcingulars) remarkably large and vaulted trapezoid. One antapical plate, quadrate to trapezoid. Apical and antapical plates flat, the latter parallel to the equatorial plane. Sutures, with the exception of some at the apex, marked by septa, that may be developed weakly to strongly and finely to coarsely. When strongly developed, the septa indicating the cingulum are only present at the antapical side. In the specimens with weakly developed crests, the projections are distally furcate. In specimens with more strongly developed septa, these septa are either finely or coarsely dentate. These forms are described as L. jurassica var. ornata. The specimen drawn shows the following tabulation: 4ap + 5pr + ?g + 5pst + 1p + 1at. The apex is sealed by an apex-platelet. I suspect that the apical plates bordering the sulcus (1" and 2") are not always separated and form the "rhomboid plate".
NOW Ctenidodinium ornatum. Originally Lithodinia jurassica var. ornata, subsequently (and now) Ctenidodinium ornatum, thirdly Gonyaulacysta ornata. Taxonomic junior synonym: Brotzenia (as Ctenidodinium?) cristata, according to Woollam (1983, p.190).
Holotype: Eisenack, 1935, pl.4, fig.9.
Age: Oxfordian. Parent: Lithodinia jurassica
Translations Eisenack, 1935: LPP
Original description: Eisenack 1935, p.175-176
Annotated description: Body mostly polyhedral and in dorsal or ventral view a slightly elongate hexagon with more or less convex sides; occasionally spherical. Hypocyst as large as or slightly higher than epicyst. Cingulum clear, but quite flat. Sulcus hardly discernible, apparently extremely flat. In equatorial section ring-shaped. Equatorial plates (pre- and postcingulars) remarkably large and vaulted trapezoid. One antapical plate, quadrate to trapezoid. Apical and antapical plates flat, the latter parallel to the equatorial plane. Sutures, with the exception of some at the apex, marked by septa, that may be developed weakly to strongly and finely to coarsely. When strongly developed, the septa indicating the cingulum are only present at the antapical side. In the specimens with weakly developed crests, the projections are distally furcate. In specimens with more strongly developed septa, these septa are either finely or coarsely dentate. These forms are described as L. jurassica var. ornata. The specimen drawn shows the following tabulation: 4ap + 5pr + ?g + 5pst + 1p + 1at. The apex is sealed by an apex-platelet. I suspect that the apical plates bordering the sulcus (1" and 2") are not always separated and form the "rhomboid plate".