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Gonyaulax margaritifera
Gonyaulax margaritifera Cookson and Eisenack, 1960
Now Impagidinium. Originally Gonyaulax, subsequently Leptodinium, thirdly (and now) Impagidinium; see also Gonyaulacysta (combination not validly published).
Holotype: Cookson and Eisenack, 1960, pl.2, fig.1; Jan du Chêne at al., 1986, pl.54, fig.6
Locus typicus: Carnarvon Basin, Western Australia
Stratum typicum: Campanian
Original description: Cookson and Eisenack, 1960, p.5
Shell small, sphaerical to slightly oval, equally divided by a distinct helicoidal girdle, epitheca and hypotheca without distinct projractions. Plates bordered by ledges, which are perforated by a single row of holes, the perforations of the wall between the holes being so thickened that in surface view the ledges appear like strings of beads. Sometimes, in small localized areas, the ledges are higher than normal and form loop-like tufts.
Dimensions: Holotype: 52 Ám long, 49 Ám broad. Range 43-52x42-49 Ám.
Now Impagidinium. Originally Gonyaulax, subsequently Leptodinium, thirdly (and now) Impagidinium; see also Gonyaulacysta (combination not validly published).
Holotype: Cookson and Eisenack, 1960, pl.2, fig.1; Jan du Chêne at al., 1986, pl.54, fig.6
Locus typicus: Carnarvon Basin, Western Australia
Stratum typicum: Campanian
Original description: Cookson and Eisenack, 1960, p.5
Shell small, sphaerical to slightly oval, equally divided by a distinct helicoidal girdle, epitheca and hypotheca without distinct projractions. Plates bordered by ledges, which are perforated by a single row of holes, the perforations of the wall between the holes being so thickened that in surface view the ledges appear like strings of beads. Sometimes, in small localized areas, the ledges are higher than normal and form loop-like tufts.
Dimensions: Holotype: 52 Ám long, 49 Ám broad. Range 43-52x42-49 Ám.