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Microdinium crinitum
Microdinium? crinitum Davey, 1969; Emendation: Below, 1987b, p.38, as Phanerodinium? crinitum
Originally (and now) Microdinium?, subsequently Phanerodinium.
Davey, 1969, questionably included this species in Microdinium.
Below, 1987, transferred the species to Phanerodinium Deflandre, 1937. Lentin and Williams, 1989, questionably retained it in Microdinium.
Holotype: Davey, 1969, pl.2, figs.8
Locus typicus: Fetchham Mill, England
Stratum typicum: Cenomanian
Original diagnosis: Davey, 1969, p. 137
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) 38 Ám, length of spines 6-19 Ám.
Original description: Davey, 1969, p. 137
The periphragm granules, which are evenly spaced on the shell surface, are up to 0.5 Ám 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. 5 Ám. The archaeopyle, although it has not been observed, is probably apical.
Originally (and now) Microdinium?, subsequently Phanerodinium.
Davey, 1969, questionably included this species in Microdinium.
Below, 1987, transferred the species to Phanerodinium Deflandre, 1937. Lentin and Williams, 1989, questionably retained it in Microdinium.
Holotype: Davey, 1969, pl.2, figs.8
Locus typicus: Fetchham Mill, England
Stratum typicum: Cenomanian
Original diagnosis: Davey, 1969, p. 137
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) 38 Ám, length of spines 6-19 Ám.
Original description: Davey, 1969, p. 137
The periphragm granules, which are evenly spaced on the shell surface, are up to 0.5 Ám 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. 5 Ám. The archaeopyle, although it has not been observed, is probably apical.