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Alterbidinium pentaradiatum
Alterbidinium? pentaradiatum, (Cookson and Eisenack, 1965), Lentin and Williams, 1985
At the time of the transfer, Lentin and Williams, 1985, questionably included this species in Alterbidinium.
Holotype: Cookson and Eisenack, 1965, pl.18, fig.1
Locus typicus: Pebble Point Formation, SW. Victoria
Stratum typicum: Paleocene
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Original description as Deflandrea pentaradiata: [Cookson and Eisenack, 1965, p. 139]:
Description:
Shell rather flat, somewhat longer than broad, with five ¦ deeply concave sides. Apical and antapical horns strongly developed; apical horn bluntly pointed; antapical horns parallel to or divergent from one another and sharply pointed. Lateral projections broad and blunt with a faintly developed notch resulting from the girdle. Wall of shell thin, smooth or with fine longitudinal striae, especially in the vicinity of the girdle (Pl. 18, fig. 2), composed of dot-like thickenings. Girdle circular, marked by two low, narrow ridges. Longitudinal furrow relatively broad, bounded by ¦ clearly marked curved ledges. In the mid-line of the ventral surface slightly below the ends of the girdle a curved slit (Pl. 18, fig. 1) with thickened edges indicative of a flagella-pore is evident in well-preserved specimens.
The capsule, while roughly oval in outline, tends to follow the outline of the shell itself; its wall is unthickened and finely, and usually faintly, granular.
The archeopyle is trapezoidal with rounded corners and extends from near the girdle to beyond the base of the apical horn.
Dimensions:
Holotype: overall length 162 µm; overall width 128 µm; capsule 86 x 95 µm.
Range: overall length 159-171 µm; overall width 116-130 µm; capsule length 76-97 µm, width 82-96 µm.
At the time of the transfer, Lentin and Williams, 1985, questionably included this species in Alterbidinium.
Holotype: Cookson and Eisenack, 1965, pl.18, fig.1
Locus typicus: Pebble Point Formation, SW. Victoria
Stratum typicum: Paleocene
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description as Deflandrea pentaradiata: [Cookson and Eisenack, 1965, p. 139]:
Description:
Shell rather flat, somewhat longer than broad, with five ¦ deeply concave sides. Apical and antapical horns strongly developed; apical horn bluntly pointed; antapical horns parallel to or divergent from one another and sharply pointed. Lateral projections broad and blunt with a faintly developed notch resulting from the girdle. Wall of shell thin, smooth or with fine longitudinal striae, especially in the vicinity of the girdle (Pl. 18, fig. 2), composed of dot-like thickenings. Girdle circular, marked by two low, narrow ridges. Longitudinal furrow relatively broad, bounded by ¦ clearly marked curved ledges. In the mid-line of the ventral surface slightly below the ends of the girdle a curved slit (Pl. 18, fig. 1) with thickened edges indicative of a flagella-pore is evident in well-preserved specimens.
The capsule, while roughly oval in outline, tends to follow the outline of the shell itself; its wall is unthickened and finely, and usually faintly, granular.
The archeopyle is trapezoidal with rounded corners and extends from near the girdle to beyond the base of the apical horn.
Dimensions:
Holotype: overall length 162 µm; overall width 128 µm; capsule 86 x 95 µm.
Range: overall length 159-171 µm; overall width 116-130 µm; capsule length 76-97 µm, width 82-96 µm.