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Gonyaulacysta tuberculata
Gonyaulacysta? tuberculata (Vozzhennikova, 1967, p.83, pl.41, figs.3a–b) Lentin and Vozzhennikova, 1990, p.99. Emendation: Lentin and Vozzhennikova, 1990, p.99, as Gonyaulacysta? tuberculata.
Originally Gonyaulax helicoidea var. tuberculata (Appendix B), subsequently Gonyaulacysta helicoidea var. tuberculata, thirdly Gonyaulacysta helicoidea subsp. tuberculata, fourthly (and now) Gonyaulacysta? tuberculata.
Lentin and Vozzhennikova, 1990, questionably included this species in Gonyaulacysta.
Holotype: Vozzhennikova, 1967, pl.41, figs.3a-b; Lentin and Vozzhennikova, text-fig.56 (lost according to Lentin and Vozzhennikova, 1990)
Neotype: Lentin and Vozzhennikova, 1990, pl.14, figs.7-8 (designated by Lentin and Vozzhennikova, 1990)
Locus typicus (Holotype): Moscow region, Russia
Stratum typicum (Holotype): Early Cretaceous
Locus typicus (Neotype): Kostromsk region, Russia
Stratum typicum (Neotype): Early Cretaceous
Translation Vozzhennikova, 1967: Lentin and Vozzhennikova, 1990
Original description: Vozzhennikova, 1967, p.99-100: Gonyaulacysta helicoidea var. tuberculata
Theca roundly ovoid and divided into two equal parts. The epitheca is bell-shaped with a small conical, bluntly ended apical horn. Transverse furrow shallow, twistet to the left, spiral and with its ends distant from each other by an amount 1-1.5 times the width of the furrow. Longitudinal furrow narrow, spirally curved. Plate formula: on the epitheca (3-4)a + 6pr + (5-6)pv; on the hypotheca 6zb + 1sr" + 1a". The apical part of the epitheca consists of 4 apical plates, of which 2a and 3a lie on the dorsal side and 1a and 4a on the ventral side. The pre-equatorial plates are often trapeziform except 6np which has the form of a right angled triangle with a strongly concave side along the longitudinal furrow. Plates 2np, 3np and 4np lie on the dorsal side ant a pylome often takes the place of 3np. Plates 1np, 5np ant 6np lie on the ventral side. Plate 1np is somewhat smaller than the others and has 1 of its sites along the ventral part of the longitudinal furrow. The hypotheca consists of 6 postequatorial plates, 1 supplementary plate ant 1 polygonal antapical plate. The postequatorial plates are trapeziform except for 1zt, which has a curved side delimiting the longitutinal furrow, and 6zt which differs from the others in its somewhat smaller dimensions. Between 1zd and the antapical plate there is a small supplementary plate. The edges of the transverse furrow and the sutures are bordered by short projections, and their surfaces, like the rest of the thecal surface, are covered with small tubercles.
Emended description: Lentin and Vozzhennikova, 1967, p.100
Cyst shape spherical to oval with a short, blunt apical horn; endocyst spherical, displaced towards the apex; bicavate to circumcavate; periphragm smooth with low rounded parasutural ridges; endophragm ornamented with randomly spaced tubercles; paratabulation faintly indicated by parasutural ridges; formula: 3-4", 6"", 6c, 5-6""", 1p, 1"""". Archeopyle formed by the loss of the third precingular paraplate, Type P, operculum free. Paracingulum indicated by two parallel longitudinal ridges with a distinct off-set on the ventral surface; parasulcus indistinct or marked by a shallow depression on the ventral surface of the hypocyst.
Size: Holotype, length 51 Ám, width 40 Ám; Neotype, length 48 Ám, width 45 Ám; width of paracingulum about 5 Ám; Range, length 48-52 Ám, width 40-45 Ám.
Originally Gonyaulax helicoidea var. tuberculata (Appendix B), subsequently Gonyaulacysta helicoidea var. tuberculata, thirdly Gonyaulacysta helicoidea subsp. tuberculata, fourthly (and now) Gonyaulacysta? tuberculata.
Lentin and Vozzhennikova, 1990, questionably included this species in Gonyaulacysta.
Holotype: Vozzhennikova, 1967, pl.41, figs.3a-b; Lentin and Vozzhennikova, text-fig.56 (lost according to Lentin and Vozzhennikova, 1990)
Neotype: Lentin and Vozzhennikova, 1990, pl.14, figs.7-8 (designated by Lentin and Vozzhennikova, 1990)
Locus typicus (Holotype): Moscow region, Russia
Stratum typicum (Holotype): Early Cretaceous
Locus typicus (Neotype): Kostromsk region, Russia
Stratum typicum (Neotype): Early Cretaceous
Translation Vozzhennikova, 1967: Lentin and Vozzhennikova, 1990
Original description: Vozzhennikova, 1967, p.99-100: Gonyaulacysta helicoidea var. tuberculata
Theca roundly ovoid and divided into two equal parts. The epitheca is bell-shaped with a small conical, bluntly ended apical horn. Transverse furrow shallow, twistet to the left, spiral and with its ends distant from each other by an amount 1-1.5 times the width of the furrow. Longitudinal furrow narrow, spirally curved. Plate formula: on the epitheca (3-4)a + 6pr + (5-6)pv; on the hypotheca 6zb + 1sr" + 1a". The apical part of the epitheca consists of 4 apical plates, of which 2a and 3a lie on the dorsal side and 1a and 4a on the ventral side. The pre-equatorial plates are often trapeziform except 6np which has the form of a right angled triangle with a strongly concave side along the longitudinal furrow. Plates 2np, 3np and 4np lie on the dorsal side ant a pylome often takes the place of 3np. Plates 1np, 5np ant 6np lie on the ventral side. Plate 1np is somewhat smaller than the others and has 1 of its sites along the ventral part of the longitudinal furrow. The hypotheca consists of 6 postequatorial plates, 1 supplementary plate ant 1 polygonal antapical plate. The postequatorial plates are trapeziform except for 1zt, which has a curved side delimiting the longitutinal furrow, and 6zt which differs from the others in its somewhat smaller dimensions. Between 1zd and the antapical plate there is a small supplementary plate. The edges of the transverse furrow and the sutures are bordered by short projections, and their surfaces, like the rest of the thecal surface, are covered with small tubercles.
Emended description: Lentin and Vozzhennikova, 1967, p.100
Cyst shape spherical to oval with a short, blunt apical horn; endocyst spherical, displaced towards the apex; bicavate to circumcavate; periphragm smooth with low rounded parasutural ridges; endophragm ornamented with randomly spaced tubercles; paratabulation faintly indicated by parasutural ridges; formula: 3-4", 6"", 6c, 5-6""", 1p, 1"""". Archeopyle formed by the loss of the third precingular paraplate, Type P, operculum free. Paracingulum indicated by two parallel longitudinal ridges with a distinct off-set on the ventral surface; parasulcus indistinct or marked by a shallow depression on the ventral surface of the hypocyst.
Size: Holotype, length 51 Ám, width 40 Ám; Neotype, length 48 Ám, width 45 Ám; width of paracingulum about 5 Ám; Range, length 48-52 Ám, width 40-45 Ám.