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Cyclonephelium downiei
Cyclonephelium downiei (Sarjeant, 1960) Ioannides et al., 1977
Now Acanthaulax?. Originally Baltisphaeridium, subsequently Acanthaulax, thirdly (and now) Acanthaulax?, fourthly Cyclonephelium.
Lentin and Williams, 1977, retained this species in Acanthaulax Sarjeant, 1968.
Sarjeant and Stover, 1978, concurred with the opinion of Lentin and Williams, 1977.
Holotype: Downiei, 1957, pl.20, fig.10 (as Hystrichosphaeridium pattei Valensi, 1949); Jan du Chêne et al., 1986, pl.3, figs.7-9
Locus typicus: France
Stratum typicum: Kimmeridgian
Original description: Downie, 1957, p. 425: Hystrichosphaeridium pattei
The test is sphaerical, 32-50 µm in diameter. There is a very large number of small processes, 4-5 µm long, forking distally into two short branches with a wide angle between. The figure indicates low ridges linking the processes.
Diagnosis: Sarjeant, 1960, p. 138: Baltisphaeridium downiei
A species of Baltisphaeridium having a spheroidal to ovoidal shell densely covered by very short spines, knobbed or briefly bifurcate, sometimes connected by low ridges on the shell surface. The spines are in number such that 70 to 90 are seen around the shell periphery: their length is of the order of one-thirtieth the longest shell diameter.
Dimensions: Type specimen: overall long diameter 50 µm, short diameter 45 µm (slightly damaged). Spines 1-1.5 µm in length. Range: overall diameters 32-50 µm.
Affinities:
Sarjeant, 1960, p. 139: Baltisphaeridium downiei
Baltisphaeridium downiei differs from Baltisphaeridium fimbriatum (White, 1842) of the Cretaceous of England, and from Baltisphaeridium cf. fimbriatum (White) Sarjeant, 1960, in the relative length of its processes, around one-thirtieth instead of one-tenth the shell diameter.
Now Acanthaulax?. Originally Baltisphaeridium, subsequently Acanthaulax, thirdly (and now) Acanthaulax?, fourthly Cyclonephelium.
Lentin and Williams, 1977, retained this species in Acanthaulax Sarjeant, 1968.
Sarjeant and Stover, 1978, concurred with the opinion of Lentin and Williams, 1977.
Holotype: Downiei, 1957, pl.20, fig.10 (as Hystrichosphaeridium pattei Valensi, 1949); Jan du Chêne et al., 1986, pl.3, figs.7-9
Locus typicus: France
Stratum typicum: Kimmeridgian
Original description: Downie, 1957, p. 425: Hystrichosphaeridium pattei
The test is sphaerical, 32-50 µm in diameter. There is a very large number of small processes, 4-5 µm long, forking distally into two short branches with a wide angle between. The figure indicates low ridges linking the processes.
Diagnosis: Sarjeant, 1960, p. 138: Baltisphaeridium downiei
A species of Baltisphaeridium having a spheroidal to ovoidal shell densely covered by very short spines, knobbed or briefly bifurcate, sometimes connected by low ridges on the shell surface. The spines are in number such that 70 to 90 are seen around the shell periphery: their length is of the order of one-thirtieth the longest shell diameter.
Dimensions: Type specimen: overall long diameter 50 µm, short diameter 45 µm (slightly damaged). Spines 1-1.5 µm in length. Range: overall diameters 32-50 µm.
Affinities:
Sarjeant, 1960, p. 139: Baltisphaeridium downiei
Baltisphaeridium downiei differs from Baltisphaeridium fimbriatum (White, 1842) of the Cretaceous of England, and from Baltisphaeridium cf. fimbriatum (White) Sarjeant, 1960, in the relative length of its processes, around one-thirtieth instead of one-tenth the shell diameter.