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Glaphyrocysta divaricata
Glaphyrocysta divaricata (Williams and Downie, 1966) Stover and Evitt, 1978
Originally Cyclonephelium, subsequently (and now) Glaphyrocysta.
Holotype: Williams and Downie, 1966, pl.25, fig.1; text-fig.60
Locus typicus: London Clay, Whitecliff, England
Stratum typicum: Early Eocene
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Glaphyrocysta divaricata (Williams and Downie, 1966c) Stover and Evitt, 1978, has processes united distally in complex fashion, sometimes by trabeculae, sometimes by perforated membranes. Erect unconnected secae, acuminate or bifid distally, arising from outer margin of trabeculae or membranes. Length of processes rarely exceeding one third of diameter of central body. Size: diameter of central body 45-71 µm, length of processes up to 15 µm.
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Original diagnosis: Williams and Downie, 1966, p. 223: Cyclonephelium divaricatum
Central body flat or slightly convex with circular outline bearing numerous ambital taeniate processes. Processes united distally in complex fashion, sometimes by trabeculae, sometimes by perforated membranes. Erect unconnected secae, acuminate or bifid distally, arising from outer margin of trabeculae or membranes. Length of processes rarely exceeding one-third the diameter of the central body.
Dimensions: Holotype: diameter of central body 54x71 µm,. Observed range: diameter of central body 45-71 µm. Length of processes up to 15 µm.
Original description: Williams and Downie, 1966, p. 224: Cyclonephelium divaricatum
The central body has a finely reticulate surface and is formed from the extremely thin endophragm. The periphragm gives rise to the taeniate processes. The numerous processes are restricted to the ambitus of the central body save on the precingulars, where the processes surround the archaeopyle margin. The processes are short, with only a few distal interconnctions. They tend to exhibit a linear orientation and are often united proximally. The secae, arising from the distal margin of the trabeculae or membranes that unite the processes, often appear to be continuations of the processes distally, whilst at other times they arise at points distant from the processes. Occasional simple acuminate processes are present on the central body.
Affinities:
Williams and Downie, 1966, 224: Cyclonephelium divaricatum
C. divaricatum differs from other described species of Cyclonephelium in the nature of the processes distally and the point of origin of the trabeculae or interconnecting membrane.
Originally Cyclonephelium, subsequently (and now) Glaphyrocysta.
Holotype: Williams and Downie, 1966, pl.25, fig.1; text-fig.60
Locus typicus: London Clay, Whitecliff, England
Stratum typicum: Early Eocene
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Glaphyrocysta divaricata (Williams and Downie, 1966c) Stover and Evitt, 1978, has processes united distally in complex fashion, sometimes by trabeculae, sometimes by perforated membranes. Erect unconnected secae, acuminate or bifid distally, arising from outer margin of trabeculae or membranes. Length of processes rarely exceeding one third of diameter of central body. Size: diameter of central body 45-71 µm, length of processes up to 15 µm.
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Original diagnosis: Williams and Downie, 1966, p. 223: Cyclonephelium divaricatum
Central body flat or slightly convex with circular outline bearing numerous ambital taeniate processes. Processes united distally in complex fashion, sometimes by trabeculae, sometimes by perforated membranes. Erect unconnected secae, acuminate or bifid distally, arising from outer margin of trabeculae or membranes. Length of processes rarely exceeding one-third the diameter of the central body.
Dimensions: Holotype: diameter of central body 54x71 µm,. Observed range: diameter of central body 45-71 µm. Length of processes up to 15 µm.
Original description: Williams and Downie, 1966, p. 224: Cyclonephelium divaricatum
The central body has a finely reticulate surface and is formed from the extremely thin endophragm. The periphragm gives rise to the taeniate processes. The numerous processes are restricted to the ambitus of the central body save on the precingulars, where the processes surround the archaeopyle margin. The processes are short, with only a few distal interconnctions. They tend to exhibit a linear orientation and are often united proximally. The secae, arising from the distal margin of the trabeculae or membranes that unite the processes, often appear to be continuations of the processes distally, whilst at other times they arise at points distant from the processes. Occasional simple acuminate processes are present on the central body.
Affinities:
Williams and Downie, 1966, 224: Cyclonephelium divaricatum
C. divaricatum differs from other described species of Cyclonephelium in the nature of the processes distally and the point of origin of the trabeculae or interconnecting membrane.