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Gonyaulax scottii
Gonyaulax scottii Cookson and Eisenack, 1958
Now Cribroperidinium?. Originally Gonyaulax, subsequently Gonyaulacysta, thirdly Millioudodinium?, fourthly (and now) Cribroperidinium?.
Holotype: Cookson and Eisenack, 1958, pl.2, fig.5; Jan du Chêne et al., 1986, pl.33, fig.5
Locus typicus: Carnavron Basin, W Australia
Stratum typicum: Early-Middle Kimmeridgian
Original description: Cookson and Eisenack, 1958, p. 30
Theca variable in shape but mostly oval; epitheca dome-shaped with sharply delimited horn, hypotheca more rounded. Wall of theca thick, prolonged at intervals into short, blunt processes and ornamented, especially in the antapical region, by rather delicate processes that are sometimes free but more often confluent forming a loosely constructed or homogeneous membrane. The transverse girdle is narrow and generally obscured by the superficial membrane as frequently are the outlines of the plates.
The tabulation has not been exactly determined but in general conforms to that characterising the genus Gonyaulax.
Dimensions: Type 147x119 Ám. Range 118-156x114-119 Ám. Apical horn 21-24 Ám.
Affinities:
Cookson and Eisenack, 1958, p. 30: In its generall features Gonyaulax scottii agrees with the European Upper Jurassic species G. cladophora Defl. but differs in its rather more elongated form and more complex type of ornamentation. In G. cladophora the spiny outgrowths delimiting the plates and furrow are free from one another, whereas in G. scottii they are usually fused distally forming a delicate membrane.
Now Cribroperidinium?. Originally Gonyaulax, subsequently Gonyaulacysta, thirdly Millioudodinium?, fourthly (and now) Cribroperidinium?.
Holotype: Cookson and Eisenack, 1958, pl.2, fig.5; Jan du Chêne et al., 1986, pl.33, fig.5
Locus typicus: Carnavron Basin, W Australia
Stratum typicum: Early-Middle Kimmeridgian
Original description: Cookson and Eisenack, 1958, p. 30
Theca variable in shape but mostly oval; epitheca dome-shaped with sharply delimited horn, hypotheca more rounded. Wall of theca thick, prolonged at intervals into short, blunt processes and ornamented, especially in the antapical region, by rather delicate processes that are sometimes free but more often confluent forming a loosely constructed or homogeneous membrane. The transverse girdle is narrow and generally obscured by the superficial membrane as frequently are the outlines of the plates.
The tabulation has not been exactly determined but in general conforms to that characterising the genus Gonyaulax.
Dimensions: Type 147x119 Ám. Range 118-156x114-119 Ám. Apical horn 21-24 Ám.
Affinities:
Cookson and Eisenack, 1958, p. 30: In its generall features Gonyaulax scottii agrees with the European Upper Jurassic species G. cladophora Defl. but differs in its rather more elongated form and more complex type of ornamentation. In G. cladophora the spiny outgrowths delimiting the plates and furrow are free from one another, whereas in G. scottii they are usually fused distally forming a delicate membrane.