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Glaphyrocysta ordinata
Glaphyrocysta ordinata (Williams and Downie, 1966) Stover and Evitt, 1978
Originally Cyclonephelium, subsequently (and now) Glaphyrocysta.
Holotype: Williams and Downie 1966, pl. 25, fig. 3, text-fig. 62
Locus typicus: London Clay, Enborne, 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 ordinata (Williams and Downie, 1966c) Stover and Evitt, 1978, has processes restricted to linear complexes regularly distributed on the central body. Reflected tabulation 4', 6", 5"’, 1p, 1"”. Processes solid, slender, taeniate, united one-half to two-thirds along their length by membranes or trabeculae. Processes distally unconnected and unequally furcate. Size: diameter of central body 41-74 µm, length of processes up to 40 µm.
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Original diagnosis: Williams and Downie, 1966, p. 225-227: Cyclonephelium ordinatum
Thin walled central body with granular surface. Processes formed from periphragm and restricted to linear complexes regularly distributed on central body.
Reflected tabulation deduced form linear complexes of 4', 6'', 5''', 1p, 1''''. Processes slender, solid, taeniate, united half to two-thirds along their length by membranes or trabeculae. Processes distally unconnected and unequally bifurcate.
Dimensions: Holotype: diameter of central body 61 by 73 Ám. Length of processes up to 36 Ám. Observed range: diameter of central body 41-74 Ám, length of processes up to 40 Ám. Number of specimens measured, 4.
Original description: Williams and Downie, 1966, p. 226-227: Cyclonephelium ordinatum
This species is unusual in that it possesses processes restricted to the ambitus yet which are grouped into linear or sometimes arcuate complexes reflecting a dinoflagellate tabulation. The apical archaeopyle is nearly always developed and had a clear sulcal notch. The precingulars possess a variable number of processes, plates 1'', 2'', 4'' and 5'' having well-developed linear complexes, 3'' having a complex of varying extent, whilst 6'' can be devoid of processes.
The processes are not unlike those of Areoligera medusettiformis (O. Wetzel, 1933). The interconnnecting membrane sometimes extends to the base of the processes and, if so developed, is often fenestrate proximally. Distally the processes are bifurcate commonly with one fork longer than the other and recurved. Occasionally the processes are acuminate. Branching can occur distally to the interconnecting membrane or trabeculae.
Affinities:
Williams and Downie, 1966, p. 226: Cyclonephelium ordinatum
C. ordinatum differs from C. divaricum in the regular arrangement of the processes in liniear complexes and the larger overall size. It is included within the genus Cyclonephelium on account of the absence of processes from the mid-dorsal and ventral surface apart from those on the margin of the archaeopyle.
Originally Cyclonephelium, subsequently (and now) Glaphyrocysta.
Holotype: Williams and Downie 1966, pl. 25, fig. 3, text-fig. 62
Locus typicus: London Clay, Enborne, England
Stratum typicum: Early Eocene
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Glaphyrocysta ordinata (Williams and Downie, 1966c) Stover and Evitt, 1978, has processes restricted to linear complexes regularly distributed on the central body. Reflected tabulation 4', 6", 5"’, 1p, 1"”. Processes solid, slender, taeniate, united one-half to two-thirds along their length by membranes or trabeculae. Processes distally unconnected and unequally furcate. Size: diameter of central body 41-74 µm, length of processes up to 40 µm.
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Original diagnosis: Williams and Downie, 1966, p. 225-227: Cyclonephelium ordinatum
Thin walled central body with granular surface. Processes formed from periphragm and restricted to linear complexes regularly distributed on central body.
Reflected tabulation deduced form linear complexes of 4', 6'', 5''', 1p, 1''''. Processes slender, solid, taeniate, united half to two-thirds along their length by membranes or trabeculae. Processes distally unconnected and unequally bifurcate.
Dimensions: Holotype: diameter of central body 61 by 73 Ám. Length of processes up to 36 Ám. Observed range: diameter of central body 41-74 Ám, length of processes up to 40 Ám. Number of specimens measured, 4.
Original description: Williams and Downie, 1966, p. 226-227: Cyclonephelium ordinatum
This species is unusual in that it possesses processes restricted to the ambitus yet which are grouped into linear or sometimes arcuate complexes reflecting a dinoflagellate tabulation. The apical archaeopyle is nearly always developed and had a clear sulcal notch. The precingulars possess a variable number of processes, plates 1'', 2'', 4'' and 5'' having well-developed linear complexes, 3'' having a complex of varying extent, whilst 6'' can be devoid of processes.
The processes are not unlike those of Areoligera medusettiformis (O. Wetzel, 1933). The interconnnecting membrane sometimes extends to the base of the processes and, if so developed, is often fenestrate proximally. Distally the processes are bifurcate commonly with one fork longer than the other and recurved. Occasionally the processes are acuminate. Branching can occur distally to the interconnecting membrane or trabeculae.
Affinities:
Williams and Downie, 1966, p. 226: Cyclonephelium ordinatum
C. ordinatum differs from C. divaricum in the regular arrangement of the processes in liniear complexes and the larger overall size. It is included within the genus Cyclonephelium on account of the absence of processes from the mid-dorsal and ventral surface apart from those on the margin of the archaeopyle.