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Cleistosphaeridium polypes

Cleistosphaeridium polypes, (Cookson and Eisenack, 1962), Davey, 1969

Originally Hystrichosphaeridium recurvatum ssp. polypes, subsequently Cleistosphaeridium polypes, thirdly Bacchidinium polypes, fourthly Impletosphaeridium polypes, fifthly Kiokansium polypes; see also Polysphaeridium? polypes (combination not validly published).
Tax. sr. synonym of Kiokansium unituberculatum (Tasch, 1964) Stover and Evitt, 1978, according to Duxbury, 1983, and Lentin and Williams, 1985, 1989. Davey, 1969, raised Hystrichosphaeridium recurvatum ssp. polypes to the species rank, as Cleistosphaeridium polypes. Therefore, at the species rank, Kiokansium unituberculatum is the taxonomic senior synonym.
Tax. sr. synonym of Cleistosphaeridium? solidum Yun, 1981, according to Below, 1982.

Holotype: Cookson and Eisenack, 1962, pl.4, figs.11-13
Locus typicus: Victoria, Australia
Stratum typicum: Albian-Cenomanian

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Original description as Hystrichosphaeridium recurvatum ssp. polypes: [Cookson and Eisenack 1962, p. 491]:

Diagnosis:
Shell circular to subcircular in outline with forty or more slender appendages of approximately uniform width throughout except for a slight broadening at the base; the tips of the appendages are fringed with short and straight or recurved processes, which divide once or twice into short, hair-like branches that are visibly only with the aid of an oil-immersion objective. The surface of the shell is finely granular.

Dimensions:
Over-all diameter ca. 52-99 µm; shell 33-57 µm ; appendages ca. 15-25 µm.

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Supplemental description as Cleistosphaeridium polypes:

Davey 1969, p. 154:

Description:
The shell is spherical to subspherical and bears numerous slender processes. The shell wall is thin and may be smooth or slightly granular. the processes are narrow, usually less than 1 µm in width for most of their length, broadening slightly proximally. They are closed distally and terminate in a number of short, fine spines. The latter are not so numerous in the English and French specimens as in those from Australia and North America where the distal spines are numerous.
A fairly large archaeopyle, probably apical, with an angular margin is often present.

Dimensions:
shell diameter 31(38.4)47 µm, maximum process length 9(13.4)18 µm.
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