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Cyclonephelium spinetum

Cyclonephelium spinetum Eaton, 1976

Now Glaphyrocysta?. Originally Cyclonephelium, subsequently (and now) Glaphyrocysta?.
Holotype: Eaton, 1976, pl.8, fig.3, text-fig.12; Bujak et al., 1980, pl.9, figs.10-11
Locus typicus: Bracklesham Beds, Whitecliff Bay, Isle of Wight, England.
Stratum typicum: Early-Middle Eocene

Original diagnosis: Eaton, 1976, p. 259
Cyst body dorsoventrally flattened with a smooth or finely granular surface. The circular or subcircular outline may be modified by the development of an antapical protuberance. Processes, restricted to the peripheral zone of the cyst body, broad and membranous, and distally expanded and united by membranous, arched trabeculae of variable width which bear numerous acuminate spines. Archaeopyle apical, tetratabular.
Dimensions: Holotype: cyst body (without operculum) 55x65 Ám; length of processes up to 22 Ám. Observed range: cyst body (without operculum) 40x55 Ám to 58x68 Ám; length of processes up to 36 Ám. (n = 10).

Affinities:
Eaton, 1976, p. 260: The membranous processes are smooth or finely striated. They show considerable variation in breadth, varying from very broad and proximally closely spaced to narrow and proximally widely spaced. The overall form of the processes is broadly T-shaped. The acuminate spines projecting from the distal trabeculae show considerable variation in length, while the trabeculae themselves vary from broad and ribbon-like to slender strands. Cyclonephelium spinetum is similar to C. Iaciniiforme Gerlach 1961 in overall form, but differs in having numerous acuminate spines projecting from the distal trabeculae. Acuminate spines are also developed in C. divaricatum Williams & Downie I966, but this species does not have the broad membranous processes which are typical of C. spinetum.
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