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Rhynchodiniopsis sarjeantii
Rhynchidiniopsis sarjeantii (Vozzhennikova, 1967) Sarjeant, 1982
Now Cribroperidinium. Originally Gonyaulax, subsequently Gonyaulacysta, thirdly Millioudodinium, fourthly Rhynchodiniopsis, fifthly Cribroperidinium?, sixthly (and now) Cribroperidinium.
Holotype: Vozzhennikova, 1967, pl.31, fig.1a; Lentin and Vozzhennikova, 1990, text-fig.53 (lost according to Lentin and Vozzhennikova, 1990)
Neotype: Vozzhennikova, 1967, pl.31, fig.3; Lentin and Vozzhennikova, 1990, pl.16, fig.4 designated by Lentin and Vozzhennikova, 1990
Locus typicus: Moscow region, Russia
Stratum typicum: Late Jurassic
Translation Vozzhennikova, 1967: Lentin and Vozzhennikova, 1990
Original description: Vozzhennikova, 1967, p.87-89: Gonyaulax sarjeantii
Theca ovoid to pyriform Epitheca larger than hypotheca. Transverse furrow equatorial, twisted to the left, its ends separated from each other by a distance corresponding to 1.5 times the width of the furrow. Longitudinal furrow expands somewhat as it approaches the antapical end. Plate formula on the epitheca - 4a + 6pr; on the hypotheca - 6zb + (1-2)sr" + 1a". Epitheca bell-shaped with a long flexible apical horn, at the distal end of which are 3 small tubercles or 3 divergent processes. The apical horn is formed as a result of the union of the 4 apical plates and their individual crests, the latter being responsible for the flexible part of the horn. The anterior apical plate is narrow and extends over two thirds the length of the epitheca; it cones into contact with the fourth apical plate and the first and sixth anterior equatorial plates, together with the longitudinal furrow. The anterior and posterior equatorial plates are large and trapeziform except for the sixth anterior and the first and sixth posterior equatorial plates which are considerably smaller than the others. The intercalary plates of the hypotheca are small. The antapical plate is polygonal or quadrangular. The margin of the transverse furrow and the edges of the plates are bounded by a finely reticulate or columnar border which is formed as a result of the fusion of slender outgrowths. The thecal armour is thick and bright yellow in color. Its surface is finely tuberculate or finely granular. A pylome takes the place of the third anterior equatorial plate.
Dimensions: Holotype: length 151.2 µm, breadth 92 µm, width of transverse furrow 5.4 µm.
Now Cribroperidinium. Originally Gonyaulax, subsequently Gonyaulacysta, thirdly Millioudodinium, fourthly Rhynchodiniopsis, fifthly Cribroperidinium?, sixthly (and now) Cribroperidinium.
Holotype: Vozzhennikova, 1967, pl.31, fig.1a; Lentin and Vozzhennikova, 1990, text-fig.53 (lost according to Lentin and Vozzhennikova, 1990)
Neotype: Vozzhennikova, 1967, pl.31, fig.3; Lentin and Vozzhennikova, 1990, pl.16, fig.4 designated by Lentin and Vozzhennikova, 1990
Locus typicus: Moscow region, Russia
Stratum typicum: Late Jurassic
Translation Vozzhennikova, 1967: Lentin and Vozzhennikova, 1990
Original description: Vozzhennikova, 1967, p.87-89: Gonyaulax sarjeantii
Theca ovoid to pyriform Epitheca larger than hypotheca. Transverse furrow equatorial, twisted to the left, its ends separated from each other by a distance corresponding to 1.5 times the width of the furrow. Longitudinal furrow expands somewhat as it approaches the antapical end. Plate formula on the epitheca - 4a + 6pr; on the hypotheca - 6zb + (1-2)sr" + 1a". Epitheca bell-shaped with a long flexible apical horn, at the distal end of which are 3 small tubercles or 3 divergent processes. The apical horn is formed as a result of the union of the 4 apical plates and their individual crests, the latter being responsible for the flexible part of the horn. The anterior apical plate is narrow and extends over two thirds the length of the epitheca; it cones into contact with the fourth apical plate and the first and sixth anterior equatorial plates, together with the longitudinal furrow. The anterior and posterior equatorial plates are large and trapeziform except for the sixth anterior and the first and sixth posterior equatorial plates which are considerably smaller than the others. The intercalary plates of the hypotheca are small. The antapical plate is polygonal or quadrangular. The margin of the transverse furrow and the edges of the plates are bounded by a finely reticulate or columnar border which is formed as a result of the fusion of slender outgrowths. The thecal armour is thick and bright yellow in color. Its surface is finely tuberculate or finely granular. A pylome takes the place of the third anterior equatorial plate.
Dimensions: Holotype: length 151.2 µm, breadth 92 µm, width of transverse furrow 5.4 µm.