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Phthanoperidinium echinatum
Phthanoperidinium echinatum Eaton, 1976
Taxonomic senior synonym: Peridinium (now Phthanoperidinium) stockmansii, according to de Coninck (1977, p.40) and by implication in Islam (1982, p.315), who considered Phthanoperidinium echinatum to be the senior name.
Taxonomic junior synonym: Phthanoperidinium? pseudoechinatum, according to Islam (1982, p.309).
Holotype: Eaton, 1976, pl.17, fig.8-9; Bujak et al., 1980, pl.5, fig.10-12
Locus typicus: Bracklesham Beds, Whitecliff Bay, Isle of Wight, England.
Stratum typicum: Early-middle Eocene
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Phthanoperidinium echinatum Eaton, 1976. Diagnosis: Cyst body has a smooth surface, and a subcircular or rounded polygonal outline modified by a short blunt apical horn. Plate boundaries accentuated by a distinctive ornament concentrated at the plate margins, consisting of short hair-like projections, each with a bulbous spherical distal termination. Cingular zone clearly defined and slightly helicoid. Reflected paratabulation peridinioid. Archeopyle formed from loss of 2a. De Coninck (1977, p.40) considered this species to be a taxonomic junior synonym of Phthanoperidinium stockmansii. Size: overall 26 x 22 to 48 x 42 µm, length of spines up to 2 µm.
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Original diagnosis: Eaton, 1976, p. 298
Cyst body has a smooth surface, and a subcircular or rounded polygonal outline modified by a short blunt apical horn. Plate boundaries accentuated by a distinctive ornament concentrated at the plate margins, consisting of short hair-like projections, each with a bulbous spherical distal termination. Cingular zone clearly defined and slightly helicoid. Reflected tabulation 4', 3a, 7", 5''', 2''''; archaeopyle intercalary, formed by displacement of plate 2a. Dimensions: Holotype: overall 29 x 22 µm; length of spines up to 2 µm. Observed range: overall 26 x 22 µm to 48 x 42 µm; length of spines up to 3 µm. (n = 26).
Affinities:
Eaton, 1976, p. 298-299: The majority of the recorded specimens are complete or exhibit an intercalary archaeopyle formed by the displacement of plate 2a. A few specimens have been observed with plate 4'' displaced as well as plate 2a, probably due to sutural weakness. The distinctive ornament of P. echinatum distinguishes this species from all described species of Phtaneroperidinium.
Taxonomic senior synonym: Peridinium (now Phthanoperidinium) stockmansii, according to de Coninck (1977, p.40) and by implication in Islam (1982, p.315), who considered Phthanoperidinium echinatum to be the senior name.
Taxonomic junior synonym: Phthanoperidinium? pseudoechinatum, according to Islam (1982, p.309).
Holotype: Eaton, 1976, pl.17, fig.8-9; Bujak et al., 1980, pl.5, fig.10-12
Locus typicus: Bracklesham Beds, Whitecliff Bay, Isle of Wight, England.
Stratum typicum: Early-middle Eocene
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Phthanoperidinium echinatum Eaton, 1976. Diagnosis: Cyst body has a smooth surface, and a subcircular or rounded polygonal outline modified by a short blunt apical horn. Plate boundaries accentuated by a distinctive ornament concentrated at the plate margins, consisting of short hair-like projections, each with a bulbous spherical distal termination. Cingular zone clearly defined and slightly helicoid. Reflected paratabulation peridinioid. Archeopyle formed from loss of 2a. De Coninck (1977, p.40) considered this species to be a taxonomic junior synonym of Phthanoperidinium stockmansii. Size: overall 26 x 22 to 48 x 42 µm, length of spines up to 2 µm.
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Original diagnosis: Eaton, 1976, p. 298
Cyst body has a smooth surface, and a subcircular or rounded polygonal outline modified by a short blunt apical horn. Plate boundaries accentuated by a distinctive ornament concentrated at the plate margins, consisting of short hair-like projections, each with a bulbous spherical distal termination. Cingular zone clearly defined and slightly helicoid. Reflected tabulation 4', 3a, 7", 5''', 2''''; archaeopyle intercalary, formed by displacement of plate 2a. Dimensions: Holotype: overall 29 x 22 µm; length of spines up to 2 µm. Observed range: overall 26 x 22 µm to 48 x 42 µm; length of spines up to 3 µm. (n = 26).
Affinities:
Eaton, 1976, p. 298-299: The majority of the recorded specimens are complete or exhibit an intercalary archaeopyle formed by the displacement of plate 2a. A few specimens have been observed with plate 4'' displaced as well as plate 2a, probably due to sutural weakness. The distinctive ornament of P. echinatum distinguishes this species from all described species of Phtaneroperidinium.