Back
Phthanoperidinium eocenicum
Pthanoperidinium? eocenicum (Cookson and Eisenack, 1965) Lentin and Williams, 1973
Originally Peridinium, subsequently (and now) Phthanoperidinium?.
Stover and Evitt (1978, p.119) considered Phthanoperidinium stockmansii and Phthanoperidinium resistente to be possible taxonomic junior synonyms of Phthanoperidinium? eocenicum.
The transfer of this species to Phthanoperidinium? is not attributable to Eaton, 1976. At the time of the transfer, Lentin and Williams, 1973 questionably included this species in Phthanoperidinium.
Holotype: Cookson and Eisenack, 1965, pl.11, figs.1-2
Locus typicus: Browns Creek Clays, SW. Victoria
Stratum typicum: Late Eocene
Original description: Cookson and Eisenack, 1965, p.119: Peridinium eocenicum
Shell small, oval, tabulated and divided almost equally by a relatively broad, helicoid girdle. Both epitheca and hypotheca with a small, solid horn. Wall of shell finely granular with or without small dot-like thickenings of variable size on the surface of the plates (Pl. 11, fig. 5). The borders of the girdle and the thin transparent ledges of the plates are lightly granular and their edges dotted with evenly spaced granules and small tubercles, or sparsely denticulate. Tabulation is of the Peridinium type, 4"?, 3[a], 7", 5""", 1p, 2"""". Plate 1" is kite-like in shape, the two upper sides of the "rhomb" being shorter than the two lower Plate 1""" is very narrow. Intercalary strips are sometimes evident. The archeopyle is relatively large, hexagonal, and intercalary.
Dimensions: Holotype c. 60 µm long, 40 µm broad. Range c. 48-62 µm long 33-48 µm broad.
Originally Peridinium, subsequently (and now) Phthanoperidinium?.
Stover and Evitt (1978, p.119) considered Phthanoperidinium stockmansii and Phthanoperidinium resistente to be possible taxonomic junior synonyms of Phthanoperidinium? eocenicum.
The transfer of this species to Phthanoperidinium? is not attributable to Eaton, 1976. At the time of the transfer, Lentin and Williams, 1973 questionably included this species in Phthanoperidinium.
Holotype: Cookson and Eisenack, 1965, pl.11, figs.1-2
Locus typicus: Browns Creek Clays, SW. Victoria
Stratum typicum: Late Eocene
Original description: Cookson and Eisenack, 1965, p.119: Peridinium eocenicum
Shell small, oval, tabulated and divided almost equally by a relatively broad, helicoid girdle. Both epitheca and hypotheca with a small, solid horn. Wall of shell finely granular with or without small dot-like thickenings of variable size on the surface of the plates (Pl. 11, fig. 5). The borders of the girdle and the thin transparent ledges of the plates are lightly granular and their edges dotted with evenly spaced granules and small tubercles, or sparsely denticulate. Tabulation is of the Peridinium type, 4"?, 3[a], 7", 5""", 1p, 2"""". Plate 1" is kite-like in shape, the two upper sides of the "rhomb" being shorter than the two lower Plate 1""" is very narrow. Intercalary strips are sometimes evident. The archeopyle is relatively large, hexagonal, and intercalary.
Dimensions: Holotype c. 60 µm long, 40 µm broad. Range c. 48-62 µm long 33-48 µm broad.