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Millioudodinium ordocavum
Millioudinium ordocavum (Duxbury, 1977) Sarjeant, 1982
Now Gonyaulacysta. Originally (and now) Gonyaulacysta, subsequently Millioudodinium.
Lentin and Williams, 1985, retained this species in Gonyaulacysta Deflandre, 1964.
Holotype: Duxbury, 1977, pl.1, figs.10,11, text-fig.12; Jan du Chêne, 1986, pl.41, figs.1-2
Locus typicus: Speeton, England
Stratum typicum: Hauterivian
Original diagnosis: Duxbury, 1977, p.37-38: Gonyaulacysta ordocava
Endophragm thin, smooth to finely granular and produced into a distinct, rounded apical prominence. Periphragm thin, finely granular, produced into a short apical horn. Tabulation 4", 6", ?6""", 1"""", outlined by very distinctive sutural crests. These are low, distally entire and of constant hight. A regulary-spaced row of perforations each about one micron in diameter occurs in each crest.
Remark:
Duxbury, 1977, p. 38: Gonyaulacysta ordocava
This is a very distinctive though uncommon species and the regulary perforate sutural crests set it apart from all others. The thinness of the body walls and the overall test suggests some affinity with G. exsanguia.
Now Gonyaulacysta. Originally (and now) Gonyaulacysta, subsequently Millioudodinium.
Lentin and Williams, 1985, retained this species in Gonyaulacysta Deflandre, 1964.
Holotype: Duxbury, 1977, pl.1, figs.10,11, text-fig.12; Jan du Chêne, 1986, pl.41, figs.1-2
Locus typicus: Speeton, England
Stratum typicum: Hauterivian
Original diagnosis: Duxbury, 1977, p.37-38: Gonyaulacysta ordocava
Endophragm thin, smooth to finely granular and produced into a distinct, rounded apical prominence. Periphragm thin, finely granular, produced into a short apical horn. Tabulation 4", 6", ?6""", 1"""", outlined by very distinctive sutural crests. These are low, distally entire and of constant hight. A regulary-spaced row of perforations each about one micron in diameter occurs in each crest.
Remark:
Duxbury, 1977, p. 38: Gonyaulacysta ordocava
This is a very distinctive though uncommon species and the regulary perforate sutural crests set it apart from all others. The thinness of the body walls and the overall test suggests some affinity with G. exsanguia.