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Hystrichosphaeridium radiculatum

Hystrichosphaeridium radiculatum Davey and Williams 1966

Now Florentinia. Originally Hystrichosphaeridium, subsequently (and now) Florentinia.
Tax. sr. synonym of Coronifera kaiseri Ashraf, 1979, according to Below, 1982.
Questionable tax. sr. synonym of Coronifera kaiseri Ashraf, 1979, according to Harker and Sarjeant in Harker et al., 1990.
Holotype: Davey and Williams, 1966, pl.8, fig.6
Locus typicus: Fetcham Mill, Surrey, England
Stratum typicum: Late Cenomanian

Original diagnosis: Davey and Williams, 1966, p. 65
Spherical to sub-spherical central body composed of reticulate endophragm and fibrous periphragm. Processes, approximately 30 in number, composed of periphragm, fibrous, mainly hollow and open distally, simple tubiform or dividing into 2 or 3 sub-parallel branches. Processes expanding slightly distally, extremities of processes entire or denticulate.
Dimensions: holotype: diameter of central body 36 by 37µm, length of processes
13-17µm. Range: diameter of central body 31-37µm, length of processes 11-17µm.

Original description: Davey and Williams, 1966, p. 65
The reticulate endophragm appears to be granular at first sight before examination in detail. Along the lengths of the processes run fibrous strands which continue on to the surface of the central body and are sometimes continuous with similar strands from neighbouring processes. The depth of the furcation of the processes varies considerably, from merely a slight distal furcation to where there appears to be two separate processes in close proximity. A rather elongate apical archaeopyle is present surrounded by 6 precingular processes. The distribution of the remainder of the processes is difficult to determine precisely.

Affinities:
Davey and Williams, 1966, p. 65: H. radiculatum is closely related to H. mantelli differing in that the branched processes are more common and the fibrils of the processes continue across the surface of the central body. The reflected tabulation of the two species is probably very similar.
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