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Florentinia radiculata
Florentinia radiculata (Davey and Williams, 1966) Davey and Verdier, 1973; emend. Davey and Verdier, 1976
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.7, fig.8; pl.9, fig.6
Locus typicus: Fetcham Mill, Surrey, England
Stratum typicum: Late Cenomanian
Original diagnosis: Davey and Williams, 1966, p. 65: Hystrichosphaeridium radiculatum
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 37 Ám, length of processes
13-17 Ám. Range: diameter of central body 31-37 Ám, length of processes 11-17 Ám.
Original description: Davey and Williams, 1966, p. 65: Hystrichosphaeridium radiculatum
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.
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Emended diagnosis: Davey and Verdier 1976, p. 318: Florentinia radiculata
The cyst is spherical to subspherical and possesses a striate to microgranular wall which bears many slender, simple, bifurcating and rarely trifurcating processes. The processes are tubiform, striate and are truncated or, more rarely, slightly recurved distally. Basically there is one process per reflected plate area; however, bifurcation may take place proximally thus giving the impression of there being two processes instead of one compound one. The simple processes are slender and gradually taper distally; they occur mainly in the apical, cingular and sulcal regions. The pre- and postcingular processes are generally compound and bifurcate proximally; rarely they are trifurcate. The antapical process is distinctive, larger than the other simple processes, and is elongate subconical to tubular. The archaeopyle is typically of the precingular (3")-apical combination type although the apical region may remain attached.
Figured specimens: From Loffre Borehole, Nord, France. Plate I, 7--9, MPK 959, 77 m depth; Turonian. Plate I, 10,11, MPK 960,131 m depth; Senonian. Plate I, 12, MPK 961, 77 m depth; Turonian
Dimensions (in.Ám):
Holotype Range
Central body diameter 36 x 37 31-37
Length of processes 13-17 11-17
Description: Davey and Verdier 1976, p. 319: Florentinia radiculata
In a poorly orientated specimen, such as the holotype, the impression is of there being many, randomly arranged narrow processes, truncated distally, some of which are joined proximally. After orientation, affected by the identification of the archaeopyle and antapical process, the processes may be seen to be arranged in an orderly manner encircling the cyst. The larger and compound processes are always in the postcingular position; beneath these and the antapical process the cyst wall is sometimes noticeably more granular.
Remarks: F. radiculata is somewhat similar to F. mantellii (Davey et Williams 1966) and is distinguished by its smaller size, slenderer processes and more deeply divided compound processes. The processes of F. mantellii are mainly broad and when compound only branch distally. With relative shortening of the processes and the addition of trifurcating pre- and postcingular processes a form similar to Silicisphaera ferox (Deflandre 1937) comb. nov. is attainable.
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Affinities:
Davey and Williams, 1966, p. 65: Hystrichosphaeridium radiculatum
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.
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.7, fig.8; pl.9, fig.6
Locus typicus: Fetcham Mill, Surrey, England
Stratum typicum: Late Cenomanian
Original diagnosis: Davey and Williams, 1966, p. 65: Hystrichosphaeridium radiculatum
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 37 Ám, length of processes
13-17 Ám. Range: diameter of central body 31-37 Ám, length of processes 11-17 Ám.
Original description: Davey and Williams, 1966, p. 65: Hystrichosphaeridium radiculatum
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.
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Emended diagnosis: Davey and Verdier 1976, p. 318: Florentinia radiculata
The cyst is spherical to subspherical and possesses a striate to microgranular wall which bears many slender, simple, bifurcating and rarely trifurcating processes. The processes are tubiform, striate and are truncated or, more rarely, slightly recurved distally. Basically there is one process per reflected plate area; however, bifurcation may take place proximally thus giving the impression of there being two processes instead of one compound one. The simple processes are slender and gradually taper distally; they occur mainly in the apical, cingular and sulcal regions. The pre- and postcingular processes are generally compound and bifurcate proximally; rarely they are trifurcate. The antapical process is distinctive, larger than the other simple processes, and is elongate subconical to tubular. The archaeopyle is typically of the precingular (3")-apical combination type although the apical region may remain attached.
Figured specimens: From Loffre Borehole, Nord, France. Plate I, 7--9, MPK 959, 77 m depth; Turonian. Plate I, 10,11, MPK 960,131 m depth; Senonian. Plate I, 12, MPK 961, 77 m depth; Turonian
Dimensions (in.Ám):
Holotype Range
Central body diameter 36 x 37 31-37
Length of processes 13-17 11-17
Description: Davey and Verdier 1976, p. 319: Florentinia radiculata
In a poorly orientated specimen, such as the holotype, the impression is of there being many, randomly arranged narrow processes, truncated distally, some of which are joined proximally. After orientation, affected by the identification of the archaeopyle and antapical process, the processes may be seen to be arranged in an orderly manner encircling the cyst. The larger and compound processes are always in the postcingular position; beneath these and the antapical process the cyst wall is sometimes noticeably more granular.
Remarks: F. radiculata is somewhat similar to F. mantellii (Davey et Williams 1966) and is distinguished by its smaller size, slenderer processes and more deeply divided compound processes. The processes of F. mantellii are mainly broad and when compound only branch distally. With relative shortening of the processes and the addition of trifurcating pre- and postcingular processes a form similar to Silicisphaera ferox (Deflandre 1937) comb. nov. is attainable.
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Affinities:
Davey and Williams, 1966, p. 65: Hystrichosphaeridium radiculatum
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.