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Laciniadinium rhombiforme
Laciniadinium rhombiforme (Vozzhennikova, 1967, p.50, pl.7, figs.1-4; pl.15, fig.5) Lentin and Vozzhennikova, 1990, p.57. Emendation: Lentin and Vozzhennikova, 1990, p.57-58, as Laciniadinium rhombiforme.
Originally Diconodinium, subsequently Diconodinium?, thirdly (and now) Laciniadinium.
Holotype: Vozzhennikova, 1967, pl.7, fig.3, pl.15, fig.5 (lost, according to Lentin and Vozzhennikova, 1990)
Neotype: Vozzhennikova, 1967, pl.7, fig.2; Lentin and Vozzhennikova, 1990, pl.10, figs.4-5, text-fig.29 (designated by Lentin and Vozzhennikova, 1990)
Locus typicus: Kazakhstan
Stratum typicum: Turonian
Translation Vozzhennikova, 1967: Lentin and Vozzhennikova, 1990
Original description: Vozzhennikova, 1967, p.50: Diconodinium rhombiforme
Theca rhomboid,somewhat asymmetrical about the longitudinal axis, the asymmetry being particularly noticeable in the hypotheca. Lateral walls straight or concave, rarely convex. Transverse furrow equatorial, broad but not deep and slightly twisted to the right. Its ends lie somewhat distant from each other and enclose a broad, slightly depressed ventral field. The epitheca is as large or slightly larger than the hypotheca. The thecal surface is smooth or finely granular and separated into large triangular areas by the ribbing. The number of these areas on the epitheca does not exceed 5-6, whereas on the hypotheca they are larger, unequal in size and form much that on one side there are 3 large triangular areas and on the other 2 small antapical and two or three irregular postequatorial areas. This causes the hypotheca to have an asymetrical appearance (cf. plate VII, fig. 1,3,4). The ridges, which delimit the areas, are smooth or finely toothed and they terminate in small spines at the edge of the transverse furrow. The epitheca ends in a small sculptured process at the distal extremity of the hypotheca in a pointed and curved spine.
Emended description: Lentin and Vozzhennikova, 1990, p.58
Cyst shape biconical with epicyst somewhat longer than bypocyst which is slightly asymmetrical, the apical horn terminates with a solid plug which bifurcates into two sharp points, the single antapical horn (?left) terminates with a small solid spine; autophragm thin, minutely granulose. Paratabulation may be expressed by discontinuous fine ridges, the archeopyle suture and paracingulum; peridinioid. Archeopyle combination type, intercalary-precingular (3I3P)@, operculum attached at the paracingulum. Paracingulum is shallow, distinct, bordered by granules and occasional very small spines. The parasulcus is indicated only by a shallow depression at the ends of the paracingulum on the ventral surface.
Size: Holotype, length 40 Ám, width 27 Ám, width of paracingulum about 4-5 Ám; Neotype, length 44 Ám, width 35 Ám. Range, length 40-50 Ám, width 24-35 Ám.
Originally Diconodinium, subsequently Diconodinium?, thirdly (and now) Laciniadinium.
Holotype: Vozzhennikova, 1967, pl.7, fig.3, pl.15, fig.5 (lost, according to Lentin and Vozzhennikova, 1990)
Neotype: Vozzhennikova, 1967, pl.7, fig.2; Lentin and Vozzhennikova, 1990, pl.10, figs.4-5, text-fig.29 (designated by Lentin and Vozzhennikova, 1990)
Locus typicus: Kazakhstan
Stratum typicum: Turonian
Translation Vozzhennikova, 1967: Lentin and Vozzhennikova, 1990
Original description: Vozzhennikova, 1967, p.50: Diconodinium rhombiforme
Theca rhomboid,somewhat asymmetrical about the longitudinal axis, the asymmetry being particularly noticeable in the hypotheca. Lateral walls straight or concave, rarely convex. Transverse furrow equatorial, broad but not deep and slightly twisted to the right. Its ends lie somewhat distant from each other and enclose a broad, slightly depressed ventral field. The epitheca is as large or slightly larger than the hypotheca. The thecal surface is smooth or finely granular and separated into large triangular areas by the ribbing. The number of these areas on the epitheca does not exceed 5-6, whereas on the hypotheca they are larger, unequal in size and form much that on one side there are 3 large triangular areas and on the other 2 small antapical and two or three irregular postequatorial areas. This causes the hypotheca to have an asymetrical appearance (cf. plate VII, fig. 1,3,4). The ridges, which delimit the areas, are smooth or finely toothed and they terminate in small spines at the edge of the transverse furrow. The epitheca ends in a small sculptured process at the distal extremity of the hypotheca in a pointed and curved spine.
Emended description: Lentin and Vozzhennikova, 1990, p.58
Cyst shape biconical with epicyst somewhat longer than bypocyst which is slightly asymmetrical, the apical horn terminates with a solid plug which bifurcates into two sharp points, the single antapical horn (?left) terminates with a small solid spine; autophragm thin, minutely granulose. Paratabulation may be expressed by discontinuous fine ridges, the archeopyle suture and paracingulum; peridinioid. Archeopyle combination type, intercalary-precingular (3I3P)@, operculum attached at the paracingulum. Paracingulum is shallow, distinct, bordered by granules and occasional very small spines. The parasulcus is indicated only by a shallow depression at the ends of the paracingulum on the ventral surface.
Size: Holotype, length 40 Ám, width 27 Ám, width of paracingulum about 4-5 Ám; Neotype, length 44 Ám, width 35 Ám. Range, length 40-50 Ám, width 24-35 Ám.