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Cooksoniella larjakiensis
Cooksoniella larjakiense, (Vozzhennikova, 1967), Harker and Sarjeant 1975
Originally Peridinium conicum var. Iarjakiensis, subsequently Palaeoperidinium deflandrei subsp. Iarjakiense, thirdly Coohsoniella larjakiensis, fourthly Palaeoperidinium larjakiense.
Tax. jr. synonyrn of Peridinium (now Palaeoperidinium) pyrophorum Ehrenberg, 1838, according to Lentin and Vozzhennikova, 1990.
Lentin and Williams, 1977, retained this taxon as a subspecies of Palaeoperidinium deflandrei Lentin and Williams, 1973.
Holotype: Vozzhennikova, 1967, pl.16, figs.1a-b; Lentin and Vozzhennikova, 1990, text-fig.32 (lost according to Lentin and Vozzhennikova, 1990).
Locus typicus: Western Siberia, Russia
Stratum typicum: Palaeocene
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Original description as Peridinium conicum var. larjakiense: [Vozzhennikova, 1967, p. 71-72]: (Translation: Lentin and Vozzhennikova, 1990):
Description:
Armour broadly pentagonal, dorso-ventrally compressed, with a small apical outgrowth (horn) and with short slightly tapering and widely separated antapical horns. Transverse furrow equatorial, its margin bounded by small processes. Position of longitudinal furrow indistinct. The armour plates are broad fields, the sculpture of which consists of alternating transverse and longitudinal striations. The surface of the armour is finely dotted or finely punctuate. On the dorsal side there is a small round or trapeziform pylome formed as a result of the loss of the third intermediate plate.
Dimensions:
Holotype, length 148.5 µm, breadth 124 µm, width of transverse furrow 8 µm. Isolated specimen.
Originally Peridinium conicum var. Iarjakiensis, subsequently Palaeoperidinium deflandrei subsp. Iarjakiense, thirdly Coohsoniella larjakiensis, fourthly Palaeoperidinium larjakiense.
Tax. jr. synonyrn of Peridinium (now Palaeoperidinium) pyrophorum Ehrenberg, 1838, according to Lentin and Vozzhennikova, 1990.
Lentin and Williams, 1977, retained this taxon as a subspecies of Palaeoperidinium deflandrei Lentin and Williams, 1973.
Holotype: Vozzhennikova, 1967, pl.16, figs.1a-b; Lentin and Vozzhennikova, 1990, text-fig.32 (lost according to Lentin and Vozzhennikova, 1990).
Locus typicus: Western Siberia, Russia
Stratum typicum: Palaeocene
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description as Peridinium conicum var. larjakiense: [Vozzhennikova, 1967, p. 71-72]: (Translation: Lentin and Vozzhennikova, 1990):
Description:
Armour broadly pentagonal, dorso-ventrally compressed, with a small apical outgrowth (horn) and with short slightly tapering and widely separated antapical horns. Transverse furrow equatorial, its margin bounded by small processes. Position of longitudinal furrow indistinct. The armour plates are broad fields, the sculpture of which consists of alternating transverse and longitudinal striations. The surface of the armour is finely dotted or finely punctuate. On the dorsal side there is a small round or trapeziform pylome formed as a result of the loss of the third intermediate plate.
Dimensions:
Holotype, length 148.5 µm, breadth 124 µm, width of transverse furrow 8 µm. Isolated specimen.