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Phthanoperidinium resistente
Phthanoperidinium resistente (Morgenroth, 1966a, p.5, pl.2, figs.1–2) Eisenack and Kjellström, 1972, p.911.
Originally Peridinium (based on motile stage), subsequently (and now) Phthanoperidinium. Stover and Evitt (1978, p.119) considered this species to be a possible taxonomic junior synonym of Phthanoperidinium eocenicum. Eaton (1976, p.294) also proposed this combination.
Holotype: Morgenroth, 1966a, pl.2, figs.1–2.
Age: early Eocene.
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Original description: [Morgenroth, 1966a] (translated from German):
Peridinium resistente n. sp.
Plate 2 Fig. 1, 2
Derivatio nominis: resistere Latin: to resist, to persist.
Holotype: The specimen shown on Plate 2 Fig. 1, 2 and preserved in specimen HF 4.
Paratypoids: In specimen no. HF 1, HF 2, HF 3.
Locus typicus: Fehmarn, Katharinenhof.
Stratum typicum: Lower Eocene (? 2).
Diagnosis: A very small species of the genus Peridinium EHRENBERG with the following tabulation scheme: ?4', ?3a, 7", 5"', 2"". Apical horn tapered like a staircase. Two tiny antapic horns. Pronounced transverse furrow. Longitudinal furrow distinct.
Description: The small, pear-shaped theca has plates with a smooth surface, with only occasional faint granulation. The plate sutures are more heavily granulated. The epitheca and hypotheca are approximately equal in size. The epitheca terminates in a stepped, tapered apical horn. The 3-4 wide, slightly depressed girdle furrow runs in a left-handed spiral pattern. The two ends are offset from each other by approximately 1 furrow width. The broad longitudinal furrow runs from the first apical plate to the antapex. Two tiny conical antapical horns rise from the two antapical plates, one of which is only vaguely indicated. The pylome is formed by the separation of plate 2a.
Remarks: Peridinium resistente n. sp. is distinguished from all previously known fossil species by its habitus, but especially by its small size.
Dimensions:2) Length 38μ (33μ/42μ), width 28μ (25μ/31μ), length of the apical horn 3μ-4μ, pyloma Ø ca. 8μ x 11μ (30 measurements). Number of specimens examined: 43.
Originally Peridinium (based on motile stage), subsequently (and now) Phthanoperidinium. Stover and Evitt (1978, p.119) considered this species to be a possible taxonomic junior synonym of Phthanoperidinium eocenicum. Eaton (1976, p.294) also proposed this combination.
Holotype: Morgenroth, 1966a, pl.2, figs.1–2.
Age: early Eocene.
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Original description: [Morgenroth, 1966a] (translated from German):
Peridinium resistente n. sp.
Plate 2 Fig. 1, 2
Derivatio nominis: resistere Latin: to resist, to persist.
Holotype: The specimen shown on Plate 2 Fig. 1, 2 and preserved in specimen HF 4.
Paratypoids: In specimen no. HF 1, HF 2, HF 3.
Locus typicus: Fehmarn, Katharinenhof.
Stratum typicum: Lower Eocene (? 2).
Diagnosis: A very small species of the genus Peridinium EHRENBERG with the following tabulation scheme: ?4', ?3a, 7", 5"', 2"". Apical horn tapered like a staircase. Two tiny antapic horns. Pronounced transverse furrow. Longitudinal furrow distinct.
Description: The small, pear-shaped theca has plates with a smooth surface, with only occasional faint granulation. The plate sutures are more heavily granulated. The epitheca and hypotheca are approximately equal in size. The epitheca terminates in a stepped, tapered apical horn. The 3-4 wide, slightly depressed girdle furrow runs in a left-handed spiral pattern. The two ends are offset from each other by approximately 1 furrow width. The broad longitudinal furrow runs from the first apical plate to the antapex. Two tiny conical antapical horns rise from the two antapical plates, one of which is only vaguely indicated. The pylome is formed by the separation of plate 2a.
Remarks: Peridinium resistente n. sp. is distinguished from all previously known fossil species by its habitus, but especially by its small size.
Dimensions:2) Length 38μ (33μ/42μ), width 28μ (25μ/31μ), length of the apical horn 3μ-4μ, pyloma Ø ca. 8μ x 11μ (30 measurements). Number of specimens examined: 43.