Back
Florentinia clavigera
Florentinia clavigera (Deflandre, 1937) emend. Davey and Verdier, 1973
Originally Hystrichosphaeridium, subsequently Baltisphaeridium), thirdly Hystrichokolpoma, fourthly (and now) Florentinia, fifthly Hystrichosphaera.
Lentin and Williams, 1989, inadvertently transferred this species to Hystrichosphaera 0. Wetzel, 1933. Lentin and Williams, 1993, retained it in Florentinia.
Holotype: Deflandre, 1937, pl.14, figs.1-2
Age: Senonian
Emended diagnosis: Davey and Verdier 1976, p. 315: Florentinia clavigera
The cyst wall is densely microgranular and bears many (approximately one process per reflected plate area) rigid, lightly striate oblate processes. These may be simple or may join proximally, rarely medially, with one or two neighbouring processes; they are relatively wide proximally, taper rapidly and are truncated distally. The processes vary in size with the finer ones occupying the cingular and sulcal regions. The antapical process is usually distinctive and varies from being tubular (closed distally) to subconical. The archaeopyle is precingular (3") and some breakage may occur along the precingular-apical plate sutures.
Figured specimens: From Loffre Borehole, Nord, France. Plate II, 7, MPK 951,105. 6 m depth; Turonian. Plate II, 8, 9, MPK 952,100 m depth; Turonian. Plate II, 10, 11, MPK 953, 127 m depth; Turonian. Plate II, 12, MPK 954, 100 m depth; Turonian.
Dimensions (in Ám): Holotype Range
Central body diameter 45 35 (49) 60
Length of processes 25-32 9 (18) 25
Description: Davey and Verdier 1976, p. 315, 316: Florentinia clavigera
The general impression of this species is of a thickish walled, granular sphere from which radiate many rigid, wide-based processes which are truncated distally. Orientation is often difficult since the operculum may remain attached and the antapical process may not be readily identifiable. However, identification of these two features allows orientation to be made and the processes can be observed to be arranged in an orderly encircling manner around the cyst. The pre- and postcingular processes are large and the sulcals, cingulars and apicals relatively smaller. Ideally only simple processes, or processes joined proximally, should be present. Rarely one or two processes are more complex and link medially. Each process, above its wide base, tapers rapidly and then more gradually distally to become approximately parallel-sided. Proximally the processes may be hollow but distally they become flattened and are not obviously hollow. Here they may be simply truncated or may expand slightly before being truncated; the process walls are thin and noticeably striate or fibrous. The cyst wall is generally more granular, and may be thicker, beneath the processes.
Remarks:Davey and Verdier 1976, p. 315, 316
F. clavigera is distinguished from other members of the genus by its moderate number of strong, broad-based processes. F. clavigera appears to be most closely related to F. Iaciniata Davey et Verdier (1973) and to F. resex sp. nov. F. clavigera can quite easily be derived from F. Iaciniata by a reduction in the number of compound, and a lack of complex, processes and a shortening of the antapical process. In fact the earlier representatives of F. clavigera do tend to have more complicated processes, thus suggesting that this species is derived from F. Iaciniata. F. resex has many more processes and the antapical process is considerably more prominent.
Originally Hystrichosphaeridium, subsequently Baltisphaeridium), thirdly Hystrichokolpoma, fourthly (and now) Florentinia, fifthly Hystrichosphaera.
Lentin and Williams, 1989, inadvertently transferred this species to Hystrichosphaera 0. Wetzel, 1933. Lentin and Williams, 1993, retained it in Florentinia.
Holotype: Deflandre, 1937, pl.14, figs.1-2
Age: Senonian
Emended diagnosis: Davey and Verdier 1976, p. 315: Florentinia clavigera
The cyst wall is densely microgranular and bears many (approximately one process per reflected plate area) rigid, lightly striate oblate processes. These may be simple or may join proximally, rarely medially, with one or two neighbouring processes; they are relatively wide proximally, taper rapidly and are truncated distally. The processes vary in size with the finer ones occupying the cingular and sulcal regions. The antapical process is usually distinctive and varies from being tubular (closed distally) to subconical. The archaeopyle is precingular (3") and some breakage may occur along the precingular-apical plate sutures.
Figured specimens: From Loffre Borehole, Nord, France. Plate II, 7, MPK 951,105. 6 m depth; Turonian. Plate II, 8, 9, MPK 952,100 m depth; Turonian. Plate II, 10, 11, MPK 953, 127 m depth; Turonian. Plate II, 12, MPK 954, 100 m depth; Turonian.
Dimensions (in Ám): Holotype Range
Central body diameter 45 35 (49) 60
Length of processes 25-32 9 (18) 25
Description: Davey and Verdier 1976, p. 315, 316: Florentinia clavigera
The general impression of this species is of a thickish walled, granular sphere from which radiate many rigid, wide-based processes which are truncated distally. Orientation is often difficult since the operculum may remain attached and the antapical process may not be readily identifiable. However, identification of these two features allows orientation to be made and the processes can be observed to be arranged in an orderly encircling manner around the cyst. The pre- and postcingular processes are large and the sulcals, cingulars and apicals relatively smaller. Ideally only simple processes, or processes joined proximally, should be present. Rarely one or two processes are more complex and link medially. Each process, above its wide base, tapers rapidly and then more gradually distally to become approximately parallel-sided. Proximally the processes may be hollow but distally they become flattened and are not obviously hollow. Here they may be simply truncated or may expand slightly before being truncated; the process walls are thin and noticeably striate or fibrous. The cyst wall is generally more granular, and may be thicker, beneath the processes.
Remarks:Davey and Verdier 1976, p. 315, 316
F. clavigera is distinguished from other members of the genus by its moderate number of strong, broad-based processes. F. clavigera appears to be most closely related to F. Iaciniata Davey et Verdier (1973) and to F. resex sp. nov. F. clavigera can quite easily be derived from F. Iaciniata by a reduction in the number of compound, and a lack of complex, processes and a shortening of the antapical process. In fact the earlier representatives of F. clavigera do tend to have more complicated processes, thus suggesting that this species is derived from F. Iaciniata. F. resex has many more processes and the antapical process is considerably more prominent.