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Gonyaulacysta ornata
Gonyaulacysta ornata (Eisenack, 1935) Pocock, 1972
Now Ctenidodinium ornatum. Originally Lithodinia jurassica var. ornata, subsequently (and now) Ctenidodinium ornatum, thirdly Gonyaulacysta ornata.
Tax. sr. synonym of Ctenidodinium? cristatum (Horowitz, 1975) Stover and Evitt, 1978, according to Woollam, 1983.
Holotype: Eisenack, 1935, pl.4, fig.9
Locus typicus of holotype: E Prussia
Stratum typicum: Oxfordian
Translations Eisenack, 1935: LPP
Original description: Eisenack 1935, p.175-176: Lithodinia jurassica var. ornata
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".
Supplemental description: Pocock, 1972, p.87-88
Vesicle longer than it is wide; epitheca hemispherical; somewhat elongate; apex smoothly rounded; no horn developed; hypotheca hemispherical; smoothly rounded, no antapical processes; transverse furrow well developed; helicoidal; longitudinal furrow usually clearly visible; widerantapically than apically; tabulation 4", 6", 6""", 1P, 1""""; archeopyle simple precingular with simple free operculum which comprises plate 3"; tabulation somewhat variable; above formula is the most complex encountered, corresponding with that in Klement"s description; other grains studied lacked included plates or possessed only five pre- or post-cingular plates; the archeopyle was only seen in aminorityof specimens; sutures reflected onto the outer layer as prominent raised crests up to 2.0 Ám wide and 3.0--5.0 Ám high; pinnate spines 1.5--5.0 Ám long with a basal width of 1.0--2.5 Ám, spaced 2.0--5.5 Ám apart line the top of the crests; similar spinose crests flank the transverse and longitudinal furrows; vesicle two-layered; capsule less than 0.5 Ám thick; smooth; appressed to outer layer; outer layer 1.0-1.5 Ám thick; smooth; ornamented with very scattered rounded granules 0.5-1.5 Ám in diameter; colour pale yellow; length of vesicle 62.7 (66.7) 71.5 Ám; length of capsule 48.0 (54.6) 60.5 Ám; width of vesicle 44.0 (60.0) 66.0 Ám; width of capsule 40.7 (48.4) 55.0 Ám.
Now Ctenidodinium ornatum. Originally Lithodinia jurassica var. ornata, subsequently (and now) Ctenidodinium ornatum, thirdly Gonyaulacysta ornata.
Tax. sr. synonym of Ctenidodinium? cristatum (Horowitz, 1975) Stover and Evitt, 1978, according to Woollam, 1983.
Holotype: Eisenack, 1935, pl.4, fig.9
Locus typicus of holotype: E Prussia
Stratum typicum: Oxfordian
Translations Eisenack, 1935: LPP
Original description: Eisenack 1935, p.175-176: Lithodinia jurassica var. ornata
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".
Supplemental description: Pocock, 1972, p.87-88
Vesicle longer than it is wide; epitheca hemispherical; somewhat elongate; apex smoothly rounded; no horn developed; hypotheca hemispherical; smoothly rounded, no antapical processes; transverse furrow well developed; helicoidal; longitudinal furrow usually clearly visible; widerantapically than apically; tabulation 4", 6", 6""", 1P, 1""""; archeopyle simple precingular with simple free operculum which comprises plate 3"; tabulation somewhat variable; above formula is the most complex encountered, corresponding with that in Klement"s description; other grains studied lacked included plates or possessed only five pre- or post-cingular plates; the archeopyle was only seen in aminorityof specimens; sutures reflected onto the outer layer as prominent raised crests up to 2.0 Ám wide and 3.0--5.0 Ám high; pinnate spines 1.5--5.0 Ám long with a basal width of 1.0--2.5 Ám, spaced 2.0--5.5 Ám apart line the top of the crests; similar spinose crests flank the transverse and longitudinal furrows; vesicle two-layered; capsule less than 0.5 Ám thick; smooth; appressed to outer layer; outer layer 1.0-1.5 Ám thick; smooth; ornamented with very scattered rounded granules 0.5-1.5 Ám in diameter; colour pale yellow; length of vesicle 62.7 (66.7) 71.5 Ám; length of capsule 48.0 (54.6) 60.5 Ám; width of vesicle 44.0 (60.0) 66.0 Ám; width of capsule 40.7 (48.4) 55.0 Ám.