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Dapsilidinium pumilum

Dapsilidinium? pumilum (Davey and Williams, 1966) Lentin and Williams, 1981

Originally Polysphaeridium, subsequently Polysphaeridium?, thirdly (and now) Dapsilidinium?.
At the time of the transfer, Lentin and Williams, 1981, questionably included this species in Dapsilidinium.
Holotype: Davey and Williams, 1966, pl.7, figs.3,4
Locus typicus: Fetcham Mill, Surrey, England
Stratum typicum: Cenomanian

Original diagnosis: Davey and Williams, 1966, p.93: Polysphaeridium pumilum
Subspherical central body having numerous small open tubular processes. Processes terminating distally in a slightly recurved more or less entire margin. Length of processes less than half that of the maximum body diameter.
Dimensions: holotype: overall diameter 40x34 µm, diameter of central body
25x19 µm, length of processes 8-10 Ám. Number of processes c.44. Range: overall
diameter 30-40 µm, diameter of central body 17-25 µm, length of processes 7-10 µm, with of processes 1-1.5 µm, number of processes 38-44.

Original description: Davey and Williams, 1966, p. 94: Polysphaeridium pumilum
The central body has a smooth surface. The processes are tubular with a thin wall. They widen slightly proximally, at the junction with the central body, and distally up to about 2 Ám. The distal termination of a process superficially strongly resembles that of Hystrichosphaeridium sheppeyi, but on closer examination the presence of spines has not been observed. The distall margin is probably entire or slightly denticulate. The number of processes present indicate that each precingular and postcingular area bears two processes. An archaeopyle has not been observed with certainty.

Affinities:
Davey and Williams, 1966, p. 94: Polysphaeridium pumilum
This species is clearly differentiated from all other species by its size and the number and type of processes present.
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