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Bacchidinium polypes

Bacchidinium polypes, (Cookson and Eisenack, 1962), Davey, 1979; Emendation: Duxbury, 1983, p.49, as Kiokansium polypes.

Originally Hystrichosphaeridium recurvatum subspieces 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 tax. sr. synonym. At the time of transfer, Davey, 1979, referred to Bacchidinium polypes polypes without reference to rank.
Tax. sr. synonym of Cleistosphaeridium solidum Yun, 1981, according to Below, 1982.

Holotype: Cookson and Eisenack, 1962b, pl.4, figs.11-13; Fensome et al., 1996, figs.1-3 - p.2283
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 descriptions:


as Cleistosphaeridium polypes: Davey, 1969, p.154:

Description:
The shell is spherical to sub-spherical 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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as Bacchidinium polypes: Davey 1979, p. 555:

Description:
The wall of the cyst is smooth to lightly punctate and being thin is often deformed.
The processes may be almost parallel-sided but often, as in the present material, they widen proximally. Distally the processes typically give rise to several small flexuous spines although in some specimens this type of termination is largely replaced by one that is recurved and non-spinose. Because both types of termination may occur on an individual specimen, specific differentiation is considered unnecessary.
The distinctive type 2P archeopyle was observed in several specimens but in the majority of cases either the shape and position of the archeopyle could not be determined or no opening at all was apparent.
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