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Sirmiodinium pseudocrystallinum
Sirmiodinium pseudocrystallinum (Beju, 1971) Courtinat, 1989
Originally Scriniodinium, subsequently Sirmiodinium.
Taxonomic senior synonym: Sirmiodinium grossii, according to Drugg (1978, p.73) and Kunz (1990, p.39).
Holotype: Beju, 1971, pl.7, fig.1
Locus typicus: Predobrudjan Depression, Karpathian Foreland, Romania
Stratum typicum: Oxfordian-Kimmeridgian
Original diagnosis: Beju, 1971, p.295: Scriniodinium pseudocrystallinum
Cavate flattened cyst with subcircular to almost pentagonal outline. Endophragm subcircular, thick walled, sometimes with a faint apical protuberance. Periphragm thinner, having a rounded apical horn flanked by two smaller lateral protuberances. Pericoel enclosing totally the endophragm, usually reduced in the apical region and more developed on the hypotract. Tabulation: 3-4?", 6", 5""", 1p, 1pv plate boundaries marked by low and narrow ridges. Cingulum wide, slightly laevorotatory; sulcus gradually widening posteriorly. Epitract/hypotract ratio about 2/3. Archaeopyle in antapical position.
Dimensions: Overall length: 68-92 µm, overall width: 65-90 µm; diameter of inner capsule: 46-73 µm.
Remark: Courtinat, 1989, p.218
Drugg (1978) considers S. pseodocrystallinum to be synonymous with S. grossii, a view adopted by Lentin and Williams (1985). These two species are distinguished in form, ornamentation of the endophragm and paratabulation formula. A large number of citations of S. grossii from Upper Jurassic sediments corresponds either to s. oxfordianum or S. pseudocrystallinum. Also, Warren (1973) describes and illustrates S. oxfordianum as being the extreme of S. grossii. Gitmez and Sarjeant (1972) depict a form called S. grossii which corresponds to S. pseudocrystallinum. S. pseudocrystallinum possesses a (tA)aPa archaeopyle, which, like that of S. oxfordianum, corresponds to the archaeopyle type of Sirmiodinium.
Originally Scriniodinium, subsequently Sirmiodinium.
Taxonomic senior synonym: Sirmiodinium grossii, according to Drugg (1978, p.73) and Kunz (1990, p.39).
Holotype: Beju, 1971, pl.7, fig.1
Locus typicus: Predobrudjan Depression, Karpathian Foreland, Romania
Stratum typicum: Oxfordian-Kimmeridgian
Original diagnosis: Beju, 1971, p.295: Scriniodinium pseudocrystallinum
Cavate flattened cyst with subcircular to almost pentagonal outline. Endophragm subcircular, thick walled, sometimes with a faint apical protuberance. Periphragm thinner, having a rounded apical horn flanked by two smaller lateral protuberances. Pericoel enclosing totally the endophragm, usually reduced in the apical region and more developed on the hypotract. Tabulation: 3-4?", 6", 5""", 1p, 1pv plate boundaries marked by low and narrow ridges. Cingulum wide, slightly laevorotatory; sulcus gradually widening posteriorly. Epitract/hypotract ratio about 2/3. Archaeopyle in antapical position.
Dimensions: Overall length: 68-92 µm, overall width: 65-90 µm; diameter of inner capsule: 46-73 µm.
Remark: Courtinat, 1989, p.218
Drugg (1978) considers S. pseodocrystallinum to be synonymous with S. grossii, a view adopted by Lentin and Williams (1985). These two species are distinguished in form, ornamentation of the endophragm and paratabulation formula. A large number of citations of S. grossii from Upper Jurassic sediments corresponds either to s. oxfordianum or S. pseudocrystallinum. Also, Warren (1973) describes and illustrates S. oxfordianum as being the extreme of S. grossii. Gitmez and Sarjeant (1972) depict a form called S. grossii which corresponds to S. pseudocrystallinum. S. pseudocrystallinum possesses a (tA)aPa archaeopyle, which, like that of S. oxfordianum, corresponds to the archaeopyle type of Sirmiodinium.