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Cyclonephelium vicinum
Cyclonephelium vicinum Eaton, 1976
Now Glaphyrocysta?. Originally Cyclonephelium, subsequently (and now) Glaphyrocysta?.
Holotype: Eaton, 1976, pl.8, fig.4, text-fig.13; Bujak et al., 1980, pl.9, figs.9,12
Locus typicus: Bracklesham Beds, Whitecliff Bay, Isle of Wight, England.
Stratum typicum: Age: Early-Middle Eocene (based on data in Bujak et al., 1980)
Original diagnosis: Eaton, 1976, p. 261
Cyst body dorsoventrally flattened with a circular or subcircular outline. The finely granular periphragm is separated from, but remains close to, the endophragm over the peripheral zone of the cyst body. The separated periphragm is wrinkled and folded. Fenestrations may be developed adjacent to, or sometimes away from, the line of separation. Archaeopyle apical, tetratabular.
Dimensions: Holotype: cyst body (without operculum) 54x67 µm; height of pericoel up to 14 µm. Observed range: cyst body (without operculum) 45x50 µm to 68x77 µm; height of pericoel up to 18 µm. (n = 18).
Affinities:
Eaton, 1976, p. 261: The development of several fenestrations in the separated periphragm adjacent to the line of separation may give the appearance of a row of distally united membranous processes. The presence of a marginal pericoel distinguishes C. vicinum from all described species of Cyclonephelium. In overall form the specimens here described are similar to those recorded from the Middle Oligocene of north Germany by Gocht (1969) as Chiropteridium aspinatum (Gerlach) Brosius 1963, but in C. vicinum the separated periphragm usually lies closer to the endophragm. The assignment of Gocht"s specimens to Chiropteridium seems questionable, and it is possible that C. vicinum may be an evolutionary predecessor of the forms described by Gocht. This problem cannot be resolved until forms of intermediate age have been studied.
Now Glaphyrocysta?. Originally Cyclonephelium, subsequently (and now) Glaphyrocysta?.
Holotype: Eaton, 1976, pl.8, fig.4, text-fig.13; Bujak et al., 1980, pl.9, figs.9,12
Locus typicus: Bracklesham Beds, Whitecliff Bay, Isle of Wight, England.
Stratum typicum: Age: Early-Middle Eocene (based on data in Bujak et al., 1980)
Original diagnosis: Eaton, 1976, p. 261
Cyst body dorsoventrally flattened with a circular or subcircular outline. The finely granular periphragm is separated from, but remains close to, the endophragm over the peripheral zone of the cyst body. The separated periphragm is wrinkled and folded. Fenestrations may be developed adjacent to, or sometimes away from, the line of separation. Archaeopyle apical, tetratabular.
Dimensions: Holotype: cyst body (without operculum) 54x67 µm; height of pericoel up to 14 µm. Observed range: cyst body (without operculum) 45x50 µm to 68x77 µm; height of pericoel up to 18 µm. (n = 18).
Affinities:
Eaton, 1976, p. 261: The development of several fenestrations in the separated periphragm adjacent to the line of separation may give the appearance of a row of distally united membranous processes. The presence of a marginal pericoel distinguishes C. vicinum from all described species of Cyclonephelium. In overall form the specimens here described are similar to those recorded from the Middle Oligocene of north Germany by Gocht (1969) as Chiropteridium aspinatum (Gerlach) Brosius 1963, but in C. vicinum the separated periphragm usually lies closer to the endophragm. The assignment of Gocht"s specimens to Chiropteridium seems questionable, and it is possible that C. vicinum may be an evolutionary predecessor of the forms described by Gocht. This problem cannot be resolved until forms of intermediate age have been studied.