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Cooksoniella paleocenica
Cooksoniella? paleocenica, (Cookson and Eisenack, 1965), Lentin and Williams, 1973
Now Ginginodinium. Originally Peridinium (a modern genus), subsequently Cooksoniella?, thirdly Palaeoperidinium, fourthly (and now) Ginginodinium.
At the time of the transfer, Lentin and Williams, 1973, questionably included this pecies in Cooksoniella.
Holotype: Cookson and Eisenack, 1965, pl.19, fig.2-3
Locus typicus: Shell bed in Pebble Point Formation, SW Victoria, Australia
Stratum typicum: Middle Paleocene
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Original description as Peridinium ?paleocenicum: [Cookson and Eisenack, 1965, p. 142]:
Description:
Shell relatively small with strongly convex: sides, the main body being almost spherical in outline.
Epitheca with a short, median apical horn of varying length and a truncate apex. Hypotheca with two broadly-based, short, blunt horns of slightly unequal lengths, the longer being on the left-hand side. Girdle equatorial, circular to slightly helicoid, broad and shallow with low but rather prominent borders.
Wall of shell thin, usually conspicuously granular to verrucose in surface view; the individual thickenings vary considerably in size and shape and are frequently longitudinally arranged, especially in and near the girdle.
The tabulation is not equally distinct in all specimens but, on the whole, is comparable with that of Peridinium. When, as in the type, it is well authenticated (Fig. 2) the rhombic plate 1", with a straight upper edge adjacent to the upper limit of the longitudinal furrow, does not reach the apex. Plates 1" and 7" are generally recognizable; the number and arrangement of the antapical plates of the ventral surface is not clear.
On the dorsal surface, plates 3", 4", 5", and 6" are evident in some specimens as well as plates 2""", 3""", 6""", and 1"""" and 2"""" (Fig. 2), while less ornamented intercalary plates are sometimes recognizable.
Dimensions:
Holotype: overall length 74 µm; overall width 67 µm.
Range-overall length 63-86 µm; overall width 52-76 µm.
Now Ginginodinium. Originally Peridinium (a modern genus), subsequently Cooksoniella?, thirdly Palaeoperidinium, fourthly (and now) Ginginodinium.
At the time of the transfer, Lentin and Williams, 1973, questionably included this pecies in Cooksoniella.
Holotype: Cookson and Eisenack, 1965, pl.19, fig.2-3
Locus typicus: Shell bed in Pebble Point Formation, SW Victoria, Australia
Stratum typicum: Middle Paleocene
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description as Peridinium ?paleocenicum: [Cookson and Eisenack, 1965, p. 142]:
Description:
Shell relatively small with strongly convex: sides, the main body being almost spherical in outline.
Epitheca with a short, median apical horn of varying length and a truncate apex. Hypotheca with two broadly-based, short, blunt horns of slightly unequal lengths, the longer being on the left-hand side. Girdle equatorial, circular to slightly helicoid, broad and shallow with low but rather prominent borders.
Wall of shell thin, usually conspicuously granular to verrucose in surface view; the individual thickenings vary considerably in size and shape and are frequently longitudinally arranged, especially in and near the girdle.
The tabulation is not equally distinct in all specimens but, on the whole, is comparable with that of Peridinium. When, as in the type, it is well authenticated (Fig. 2) the rhombic plate 1", with a straight upper edge adjacent to the upper limit of the longitudinal furrow, does not reach the apex. Plates 1" and 7" are generally recognizable; the number and arrangement of the antapical plates of the ventral surface is not clear.
On the dorsal surface, plates 3", 4", 5", and 6" are evident in some specimens as well as plates 2""", 3""", 6""", and 1"""" and 2"""" (Fig. 2), while less ornamented intercalary plates are sometimes recognizable.
Dimensions:
Holotype: overall length 74 µm; overall width 67 µm.
Range-overall length 63-86 µm; overall width 52-76 µm.