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Phanerodinium crinitum
Phanerodinium crinitum (Davey, 1969) Below, 1987; emend. Below, 1987
Now Microdinium?. Originally (and now) Microdinium?, subsequently Phanerodinium. Lentin and Williams, 1989 questionably retained the species in Microdinium Cookson and Eisenack, 1960. At the time of the transfer, Below, 1987 questionably included this species in Phanerodinium.
Holotype: Davey, 1969, pl.2, figs.7-8
Locus typicus: Fetchham Mill
Stratum typicum: Cenomanian
Original diagnosis: Davey, 1969, p. 137: Microdinium crinitum
Shell subspherical, periphragm granular and giving rise to numerous, finc, flexuous spines. Sutural crests low, bearing numerous spines. Cingulum wide, composed of elongate plates. Epitract smaller than hypotract. Archaeopyle not normally visible.
Dimensions: shell diameter 24 (30.1) 38µ, length of spines 6--19µ.
Original description: Davey, 1969, p. 137: Microdinium crinitum
The periphragm granules, which are evenly spaced on the shell surface, are up to 0.5µm high, and often form the bases of the hair-like spines. The latter tend to be especially concentrated along the sutures, and because of this tendency and the spherical form of the shell, it has not been possible to fully formulate a tabulation. However, precingular, cingular and postcingular plates are quite obvious when the orientation is favourable, the precingular plates being smaller than the postcingular plates. The cingulum is broad, c. 5µm. The archaeopyle, although it has not been observed, is probably apical.
Now Microdinium?. Originally (and now) Microdinium?, subsequently Phanerodinium. Lentin and Williams, 1989 questionably retained the species in Microdinium Cookson and Eisenack, 1960. At the time of the transfer, Below, 1987 questionably included this species in Phanerodinium.
Holotype: Davey, 1969, pl.2, figs.7-8
Locus typicus: Fetchham Mill
Stratum typicum: Cenomanian
Original diagnosis: Davey, 1969, p. 137: Microdinium crinitum
Shell subspherical, periphragm granular and giving rise to numerous, finc, flexuous spines. Sutural crests low, bearing numerous spines. Cingulum wide, composed of elongate plates. Epitract smaller than hypotract. Archaeopyle not normally visible.
Dimensions: shell diameter 24 (30.1) 38µ, length of spines 6--19µ.
Original description: Davey, 1969, p. 137: Microdinium crinitum
The periphragm granules, which are evenly spaced on the shell surface, are up to 0.5µm high, and often form the bases of the hair-like spines. The latter tend to be especially concentrated along the sutures, and because of this tendency and the spherical form of the shell, it has not been possible to fully formulate a tabulation. However, precingular, cingular and postcingular plates are quite obvious when the orientation is favourable, the precingular plates being smaller than the postcingular plates. The cingulum is broad, c. 5µm. The archaeopyle, although it has not been observed, is probably apical.