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Polysphaeridium laminaspinosum
Polysphaeridium laminaspinosum Davey and Williams, 1966
Now Dapsilidinium. Originally Polysphaeridium, subsequently (and now) Dapsilidinium.
Holotype: Davey and Williams, 1966, pl.8, fig.8
Locus typicus: Fetcham Mill, Surrey, England
Stratum typicum: Cenomanian
Original diagnosis: Davey and Williams, 1966, p. 94
Spherical to sub-spherical central body composed of reticulate endophragm. Processes numerous, approximately 36 in number, composed of periphragm; cylindrical, smooth and delicate, terminating in entire margin. Characteristic circular impression occurring where process arises from central body.
Dimensions: holotype: diameter of central body 27 by 27µm, length of processes 11-15µm, number of processes 36. Range; diameter of central body 23-28µm, length
of processes 11-17µm.
Original description: Davey and Williams, p. 94
The endophragm appears to be granular until examined under high magnification when the reticulate nature becomes apparent. The processes are broadly tubular, up to 5µm in width, usually flattened and are often bent. A few of the processes are clearly truncated at their distal extremity, but most splay out slightly and have a corrugated entire margin. A 6-sided apical archaeopyle has been observed in one specimen. The number of processes present indicate that there are two per plate.
Now Dapsilidinium. Originally Polysphaeridium, subsequently (and now) Dapsilidinium.
Holotype: Davey and Williams, 1966, pl.8, fig.8
Locus typicus: Fetcham Mill, Surrey, England
Stratum typicum: Cenomanian
Original diagnosis: Davey and Williams, 1966, p. 94
Spherical to sub-spherical central body composed of reticulate endophragm. Processes numerous, approximately 36 in number, composed of periphragm; cylindrical, smooth and delicate, terminating in entire margin. Characteristic circular impression occurring where process arises from central body.
Dimensions: holotype: diameter of central body 27 by 27µm, length of processes 11-15µm, number of processes 36. Range; diameter of central body 23-28µm, length
of processes 11-17µm.
Original description: Davey and Williams, p. 94
The endophragm appears to be granular until examined under high magnification when the reticulate nature becomes apparent. The processes are broadly tubular, up to 5µm in width, usually flattened and are often bent. A few of the processes are clearly truncated at their distal extremity, but most splay out slightly and have a corrugated entire margin. A 6-sided apical archaeopyle has been observed in one specimen. The number of processes present indicate that there are two per plate.