Back
Deflandrea dartmooria
Deflandrea dartmooria Cookson and Eisenack, 1965
Now Cerodinium. Originally Deflandrea, subsequently (and now) Cerodinium. See also Ceratiopsis (combination illegitimate).
Holotype: Cookson and Eisenack, 1965, pl.16, figs.1,2, text-fig.1
Locus typicus: Dartmoor Formation, Victoria, Australia
Stratum typicum: Palaeocene
Original description: Cookson and Eisenack, 1965, p. 133-134
Shells rather flat, nearly twice as long as broad and well tabulated, the surfaces of the plates ornamented with small dot-like thickenings. Epitheca longer than hypotheca, triangular in outline gradually narrowing to a well-developed, bluntly pointed horn. Hypotheca with almost paralell sides, a concave base and two well-developed pointed horns. Girdle distinct, slightly helicoid with finely denticulate edges. Longitudinal furrow broad, nearly straight-sided, its borders sometimes extending almost to the tips of the antapical horns. In the middle of the furrow the concavo-convex thicking in the vicinity of the flagella-pore, noted as occuring in three other Australian species od Dinophycaea (Cookson and Eisenack, 1955), is always conspicuous.
The tabulation, although always present, is not completely identifiable. The apical horn appears to be formed by four long apical plates beneath which are intercalary plates of which the largest, 2a, forms the hexagonal, precingular archaeopyle. The precingular plates number six or possibly seven with 4"" a broad plate in the middle of the dorsal surface. The postcingular plates are five or possibly six with 3""" strongly developed. The antapical plates 1"""" and 2"""" are restricted to the lower halfs of the antapical horns. Thus the approximation arrived at is 4", 4a, 6(or 7)"", 5 (or 6)""", 2"""". The sutures are made by clear breaks,as at the borders of the antapical horns.
Dimensions: Holotype 152 µm long, 80 µm broad; capsule 62-68 µm. Range 119-152 µm long, 79-95 µm broad.
Now Cerodinium. Originally Deflandrea, subsequently (and now) Cerodinium. See also Ceratiopsis (combination illegitimate).
Holotype: Cookson and Eisenack, 1965, pl.16, figs.1,2, text-fig.1
Locus typicus: Dartmoor Formation, Victoria, Australia
Stratum typicum: Palaeocene
Original description: Cookson and Eisenack, 1965, p. 133-134
Shells rather flat, nearly twice as long as broad and well tabulated, the surfaces of the plates ornamented with small dot-like thickenings. Epitheca longer than hypotheca, triangular in outline gradually narrowing to a well-developed, bluntly pointed horn. Hypotheca with almost paralell sides, a concave base and two well-developed pointed horns. Girdle distinct, slightly helicoid with finely denticulate edges. Longitudinal furrow broad, nearly straight-sided, its borders sometimes extending almost to the tips of the antapical horns. In the middle of the furrow the concavo-convex thicking in the vicinity of the flagella-pore, noted as occuring in three other Australian species od Dinophycaea (Cookson and Eisenack, 1955), is always conspicuous.
The tabulation, although always present, is not completely identifiable. The apical horn appears to be formed by four long apical plates beneath which are intercalary plates of which the largest, 2a, forms the hexagonal, precingular archaeopyle. The precingular plates number six or possibly seven with 4"" a broad plate in the middle of the dorsal surface. The postcingular plates are five or possibly six with 3""" strongly developed. The antapical plates 1"""" and 2"""" are restricted to the lower halfs of the antapical horns. Thus the approximation arrived at is 4", 4a, 6(or 7)"", 5 (or 6)""", 2"""". The sutures are made by clear breaks,as at the borders of the antapical horns.
Dimensions: Holotype 152 µm long, 80 µm broad; capsule 62-68 µm. Range 119-152 µm long, 79-95 µm broad.