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Lejeunecysta psuchra
Lejeunecysta psuchra Matsuoka, 1987, p.60-61, pl.9, figs.7-8; pl.14, figs.11-12.
Holotype: Matsuoka, 1987, pl.9, figs.7-8.
Age: Holocene.
Original description (Matsuoka, 1987):
Lejeunecysta psuchra sp. nov. Plate 9, figures 7-8 ; Plate 14, figures ll-12
Derivation of name : Greek psuchros, cold ; with reference to the ecology of this species.
Diagnosis : Lage pentagonal cysts lightly brownish-pigmented, and composed of thin autophragm without any ornamentation. Epicyst roundly conical with broad apical projection and hypocyst widely trapezoidal in dorso-ventral view with two broad and round antapical horns. Paracingulum weakly suggested by shallow indentation and indistinctive. Parasulcus indicated by moderate depression of the wall. Antapical depression between two horns also shallow to moderate. Archeopyle intercalary, but its shape unclear, because of the autophragm easily deformed.
Holotype: Alide no. AK2-2 (87.6/37.0) ; PL 9, figs. 7-8, Sample no. Ak2, Recent sediment in Akkeshi Bay, Hokkaido, North Japan.
Dimensions : Cyst length 80-84 µm, width 68-72 µm (Holotype 80 µm x 70 µm)
Number of specimens observed : 5.
Remarks : This species is somewhat similar to Votadinium carvum, but differs from the latter in having a paracingulum and two distinctive antapical horns. This cyst also resembles Lejeunecysta concreta (Reid) comb. nov. in bearing a pentagonal outline, but also differs in possessing broader antapical horns, and larger and wider hypocyst.
Equivalent thecate form : Unknown, but probably a species of Protoperidinium, because of its brownish pigmentation and intercalary archeopyle.
Holotype: Matsuoka, 1987, pl.9, figs.7-8.
Age: Holocene.
Original description (Matsuoka, 1987):
Lejeunecysta psuchra sp. nov. Plate 9, figures 7-8 ; Plate 14, figures ll-12
Derivation of name : Greek psuchros, cold ; with reference to the ecology of this species.
Diagnosis : Lage pentagonal cysts lightly brownish-pigmented, and composed of thin autophragm without any ornamentation. Epicyst roundly conical with broad apical projection and hypocyst widely trapezoidal in dorso-ventral view with two broad and round antapical horns. Paracingulum weakly suggested by shallow indentation and indistinctive. Parasulcus indicated by moderate depression of the wall. Antapical depression between two horns also shallow to moderate. Archeopyle intercalary, but its shape unclear, because of the autophragm easily deformed.
Holotype: Alide no. AK2-2 (87.6/37.0) ; PL 9, figs. 7-8, Sample no. Ak2, Recent sediment in Akkeshi Bay, Hokkaido, North Japan.
Dimensions : Cyst length 80-84 µm, width 68-72 µm (Holotype 80 µm x 70 µm)
Number of specimens observed : 5.
Remarks : This species is somewhat similar to Votadinium carvum, but differs from the latter in having a paracingulum and two distinctive antapical horns. This cyst also resembles Lejeunecysta concreta (Reid) comb. nov. in bearing a pentagonal outline, but also differs in possessing broader antapical horns, and larger and wider hypocyst.
Equivalent thecate form : Unknown, but probably a species of Protoperidinium, because of its brownish pigmentation and intercalary archeopyle.