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Phelodinium tricuspe
Phelodinium tricuspe (Wetzel, 1933a, p.166, pl.2, fig.14) Stover and Evitt, 1978, p.118. Emendation: Lejeune-Carpentier and Sarjeant, 1981, p.20, as Lejeunecysta tricuspis.
Holotype: Wetzel, 1933a, pl.2, fig.14; Lejeune-Carpentier, 1942, fig.21; Lejeune-Carpentier and Sarjeant, 1981, pl.6, fig.5. Originally Peridinium (Appendix B), subsequently Lejeunia (combination illegitimate), thirdly Astrocysta, fourthly Senegalinium, fifthly Lejeunecysta, sixthly (and now) Phelodinium. Taxonomic junior synonym: Lejeunia (now Phelodinium) kozlowskii, according to Harker and Sarjeant (1975, p.223) — however, Lindgren (1984, p.181) retained Phelodinium kozlowskii. Age: Senonian.
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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.
Phelodinium tricuspe (O.Wetzel, 1933a) Stover and Evitt, 1978, emend. Lejeune-Carpentier and Sarjeant, 1981. Lejeune-Carpentier and Sarjeant (1981, p.20) emended the diagnosis as follows, Proximate cyst of relatively large size, dorsoventrally compressed and hollowed in the ventral region. Ambitus asymmetrically pentagonal, all flanks being strongly concave. Phragma apparently composed of a single layer (autophragm). Apical horn long, slender and pointed. Antapical horns of similar size and shape, long, pointed, slightly broader based than the apical horn. Cyst prolonged equatorially at the line of the cingulum into two hornlike extensions, imparting an overall five-horned appearance to the cyst. Cingulum narrow, only feebly laevorotatory, bordered by low but well-marked ridges. Ridges or folds of the autophragm partially outline a peridinioid tabulation. In addition the cyst is ornamented with longitudinal striations. Size: holotype length 116 µm, length of apical horn 28 µm, length of antapical horns ca. 22.5 µm, maximum width 82 µm, thickness 22 µm.
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Supplemental description: Hultberg, 1985, p. 140-141
Cornucavate cyst, composed of endopl-ragm and periphragm, separated by pericoels at apical and antapical horns. The surface of the endophragm is smooth. The surface of the periphragm is smooth, and commonly folded. The shape of the cyst is peridinioid, with one, abruptly terminated apical horn, and two almost symmetrical antapical horns. The lateral sides of the cyst are concave.
No indication of paratabulation is present, except archeopyle. The archeopyle is intercalary, type I, formed by the derachment of paraplate ?a. Operculum is free on most specimens. The adantapical archeopyle margin is located very close to the paracingulum, which gives the archeopyle a precingular appearance. Paracingulum is clearly indicated by folds in the periphragm, and is almost circular.
Parasulcus is weakly indicated by folds in the periphragm.
Size - 122-140 µm (length), 95-128 µm (breadth).
Holotype: Wetzel, 1933a, pl.2, fig.14; Lejeune-Carpentier, 1942, fig.21; Lejeune-Carpentier and Sarjeant, 1981, pl.6, fig.5. Originally Peridinium (Appendix B), subsequently Lejeunia (combination illegitimate), thirdly Astrocysta, fourthly Senegalinium, fifthly Lejeunecysta, sixthly (and now) Phelodinium. Taxonomic junior synonym: Lejeunia (now Phelodinium) kozlowskii, according to Harker and Sarjeant (1975, p.223) — however, Lindgren (1984, p.181) retained Phelodinium kozlowskii. Age: Senonian.
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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.
Phelodinium tricuspe (O.Wetzel, 1933a) Stover and Evitt, 1978, emend. Lejeune-Carpentier and Sarjeant, 1981. Lejeune-Carpentier and Sarjeant (1981, p.20) emended the diagnosis as follows, Proximate cyst of relatively large size, dorsoventrally compressed and hollowed in the ventral region. Ambitus asymmetrically pentagonal, all flanks being strongly concave. Phragma apparently composed of a single layer (autophragm). Apical horn long, slender and pointed. Antapical horns of similar size and shape, long, pointed, slightly broader based than the apical horn. Cyst prolonged equatorially at the line of the cingulum into two hornlike extensions, imparting an overall five-horned appearance to the cyst. Cingulum narrow, only feebly laevorotatory, bordered by low but well-marked ridges. Ridges or folds of the autophragm partially outline a peridinioid tabulation. In addition the cyst is ornamented with longitudinal striations. Size: holotype length 116 µm, length of apical horn 28 µm, length of antapical horns ca. 22.5 µm, maximum width 82 µm, thickness 22 µm.
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Supplemental description: Hultberg, 1985, p. 140-141
Cornucavate cyst, composed of endopl-ragm and periphragm, separated by pericoels at apical and antapical horns. The surface of the endophragm is smooth. The surface of the periphragm is smooth, and commonly folded. The shape of the cyst is peridinioid, with one, abruptly terminated apical horn, and two almost symmetrical antapical horns. The lateral sides of the cyst are concave.
No indication of paratabulation is present, except archeopyle. The archeopyle is intercalary, type I, formed by the derachment of paraplate ?a. Operculum is free on most specimens. The adantapical archeopyle margin is located very close to the paracingulum, which gives the archeopyle a precingular appearance. Paracingulum is clearly indicated by folds in the periphragm, and is almost circular.
Parasulcus is weakly indicated by folds in the periphragm.
Size - 122-140 µm (length), 95-128 µm (breadth).