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Leptodinium amabile
Leptodinium? amabile (Deflandre, 1939b, p.143, pl.6, fig.8) Sarjeant, 1969, p.12. Emendation: Kunz, 1990, p.18–19, as Leptodinium amabile.
Originally Gonyaulax, subsequently Gonyaulacysta, thirdly Leptodinium, fourthly (and now) Leptodinium?. Dodekova, 1971, transferred this species to Gonyaulacysta Deflandre, 1964. Lentin and Williams, 1973, retained it in Leptodinium. Stover and Evitt, 1978, and Jan du Chêne et al., 1986, considered this to be a problematical species of Leptodinium. Sarjeant, 1982, considered this to be a provisionally accepted species of Leptodinium.
Holotype: Deflandre, 1939, pl.6, fig.8; Jan du Chêne et al., 1986, pl.69, figs.1-3
Age: Kimmeridgian
Emended description: Kunz, 1990, p.18
Proximochorate cyst with ovoidale to rounded subpolygonal shape. Areation formula: 2pr, 4", 1a, 6"", 6c, 6""", 1p, 1ps, 1"""". Archaeopyle precingular, 3""; operculum secate. Epi- anf hypocyst of nearly equal size, seperated by the strongly spiral cingulum. Sulcus extremely long. The reduced 6" is triangular, 4" quadrat and small. One intercalary area is located between 2", 3" and 3"". 1""" is relatively narrow. The large antapical area is sexiform. On the triple-point of 1", 4" and one precingular area the porichnion is situated. Finis marked by low (up to 5 Ám), finely denticulate or smooth ridges. Cyst surface psilate to chagrinate. A small number of intraareate tuberculae cover the areae, except the cingulum and sulcus.
Dimensions: length 38-46 Ám, range 43 Ám, breadth 35-42 Ám, range 37 Ám.
Originally Gonyaulax, subsequently Gonyaulacysta, thirdly Leptodinium, fourthly (and now) Leptodinium?. Dodekova, 1971, transferred this species to Gonyaulacysta Deflandre, 1964. Lentin and Williams, 1973, retained it in Leptodinium. Stover and Evitt, 1978, and Jan du Chêne et al., 1986, considered this to be a problematical species of Leptodinium. Sarjeant, 1982, considered this to be a provisionally accepted species of Leptodinium.
Holotype: Deflandre, 1939, pl.6, fig.8; Jan du Chêne et al., 1986, pl.69, figs.1-3
Age: Kimmeridgian
Emended description: Kunz, 1990, p.18
Proximochorate cyst with ovoidale to rounded subpolygonal shape. Areation formula: 2pr, 4", 1a, 6"", 6c, 6""", 1p, 1ps, 1"""". Archaeopyle precingular, 3""; operculum secate. Epi- anf hypocyst of nearly equal size, seperated by the strongly spiral cingulum. Sulcus extremely long. The reduced 6" is triangular, 4" quadrat and small. One intercalary area is located between 2", 3" and 3"". 1""" is relatively narrow. The large antapical area is sexiform. On the triple-point of 1", 4" and one precingular area the porichnion is situated. Finis marked by low (up to 5 Ám), finely denticulate or smooth ridges. Cyst surface psilate to chagrinate. A small number of intraareate tuberculae cover the areae, except the cingulum and sulcus.
Dimensions: length 38-46 Ám, range 43 Ám, breadth 35-42 Ám, range 37 Ám.