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Renidinium vitilare
Renidinium vitilare (Cookson, 1965) Stover and Evitt, 1978
Originally Cyclonephelium, subsequently (and now) Renidinium.
Holotype: Cookson, 1965, pl. 24, figs.1-2
Locus typicus: Pebble Point Formation, SW. Victoria
Stratum typicum: Paleocene
Original description: Cookson, 1965, p.138: Cyclonephelium vitilare
Shell dorsiventral, almost circular in outline with a short, blunt, apical prominence, ornamented with slightly raised, granular lace-like expansions which extend for short distances beyond the margins. The width of the ornament differs on the two surfaces, being wider and the unornamented central portion correspondingly smaller on the "dorsal" than on the "ventral" surface. Additionally, the ornament of the dorsal surface narrows distally to form two rounded, hollow, antapical projections one on each side of the mid-line. The ventral surface is characterized by the larger size of the unornamented portion and the presence of two or three + prominent, tangentially directed antapical ridges (Pl. 24, fig. 6, 7).
The cover of the archeopyle is marked into three areas by low circular ridges Pl. 24, fig. 5) . The shell-membrane is thin c. 1,5 µm and finely and closely granular; several V-shaped notches are evident around the edge after the removal of the archeopyle cover.
Dimensions: Holotype--overall length 110 µm; overall width 98 µm, width of shell 92 µm. Range in complete specimens--overall length 98-112 µm; overall width 8-102 µm.
Affinities:
Cookson, 1965, p.139: Cyclonephelium vitilare
C. vitilare can be distinguished from the described species of Cyclonephelium by the dorsiventrality of the shell and the characteristic type of ornament which seems to have resulted from the flattening, fusion, and perforation of low, much-branched ridges.
Originally Cyclonephelium, subsequently (and now) Renidinium.
Holotype: Cookson, 1965, pl. 24, figs.1-2
Locus typicus: Pebble Point Formation, SW. Victoria
Stratum typicum: Paleocene
Original description: Cookson, 1965, p.138: Cyclonephelium vitilare
Shell dorsiventral, almost circular in outline with a short, blunt, apical prominence, ornamented with slightly raised, granular lace-like expansions which extend for short distances beyond the margins. The width of the ornament differs on the two surfaces, being wider and the unornamented central portion correspondingly smaller on the "dorsal" than on the "ventral" surface. Additionally, the ornament of the dorsal surface narrows distally to form two rounded, hollow, antapical projections one on each side of the mid-line. The ventral surface is characterized by the larger size of the unornamented portion and the presence of two or three + prominent, tangentially directed antapical ridges (Pl. 24, fig. 6, 7).
The cover of the archeopyle is marked into three areas by low circular ridges Pl. 24, fig. 5) . The shell-membrane is thin c. 1,5 µm and finely and closely granular; several V-shaped notches are evident around the edge after the removal of the archeopyle cover.
Dimensions: Holotype--overall length 110 µm; overall width 98 µm, width of shell 92 µm. Range in complete specimens--overall length 98-112 µm; overall width 8-102 µm.
Affinities:
Cookson, 1965, p.139: Cyclonephelium vitilare
C. vitilare can be distinguished from the described species of Cyclonephelium by the dorsiventrality of the shell and the characteristic type of ornament which seems to have resulted from the flattening, fusion, and perforation of low, much-branched ridges.