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Florentinia ferox
Florentinia ferox, (Deflandre, 1937), Duxbury, 1980
Originally Hystrichosphaeridium, subsequently Baltisphaeridium, thirdly Hystrichokolpoma, fourthly Silicisphaera, fifthly (and now) Florentinia.
Holotype: Deflandre, 1937, pl.14, figs.3-4
Stratum typicum: Senonian
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Emended descriptions:
as Hystrichokolpoma ferox: Davey, 1969, p. 159:
Diagnosis:
Shell subspherical, densely granular or reticulate.
Processes thin walled, granular, often striated, of three kinds: (i) 6 large precingular and 4 large postcingular, possessing wide bases and tapering distally giving rise to 2 or more tubules, typically open; (ii) a single long tubular antapical process and (iii) cingular and sulcal processes, of moderate length, slender and tubular, only joining proximally if at all.
Archaeopyle apical.
Description:
H. ferox appears to be a fairly variable species. In some specimens the tabulation is not clearly indicated by the processes which tend to be smaller and may even be closed distally. However, the processes usually are well developed, their bases covering an area of the shell surface which is often slightly raised and of the same shape as a thecal plate. The precingular and postcingular processes are largest and give rise distally to as many as 10 tubules. Each cingular process divides proximally into 2 or 3 long slender tubules aligned along the cingulum. The sulcal processes may proximally divide into two tubules or may consist of a single tubule which is sometimes reduced and closed distally. The antapical process is long, tubular, open distally and terminates with a smooth or serrate margin.
Dimensions:
Holotype: length of shell 46 µm, width 36 µm, overall length 78 µm, length of processes 15-17 µm.
Range of Cenomanian specimens: diameter of central body 39(46.1)56 µm, maximum length of processes 27(30.2)36 µm. Number of specimens measured, 13.
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as Silicisphaera ferox: Davey and Verdier, 1976, p. 322-325:
Diagnosis:
The cyst is spherical to subspherical and is thick-walled and densely granular, particularly beneath the processes. The processes are relatively short, weak, and approximately of equal length; they are thin-walled, faintly striate, truncated distally and number one per reflected plate area. The base of each process is broad and covers much of the plate area. There are basically three types of processes: (1) simple, elongate subconical, (2) compound, bifurcating medially; and (3) compound, trifurcating medially. The latter type occupy the pre- and postcingular regions only. The simple and bifurcating processes occupy the apical, cingular, sulcal and antapical regions. The antapical process is not distinctively large.
The archaeopyle is of the combination type: precingular plate 3" is lost and there is a separation of the apical and precingular plates along the plate boundaries, although the apical region typically remains in position, being attached in the ventral region.
Description:
S. ferox comb. nov. is characterized by its relatively thick, granular wall and rather weak, simple, bifurcating and trifurcating processes. A typical example was illustrated by Evitt (1967, pl. 8, figs. 1-5). The cyst wall appears usually to be thicker and more granular beneath the processes giving the impression that the processes are situated on islands between which run the thinner and lower ornamented sutural areas. The simple processes are typical of the genus, being wide proximally, tapering rapidly at first then more gradually; distally they always appear to be truncated. Bifurcation and trifurcation of the larger compound processes take place approximately half way along their length.
Dimensions (in µm):
Holotype:
Central body diameter 36 x 46
Length of processes 15-17
Overall diameter 78
Remarks:
S. ferox and its generic allocation were discussed by Davey and Verdier (1973) who concluded, at that time, that until additional evidence was available no generic reallocation was possible. Now, after considerable further study of this species and of related species it is clear that, although the affinities of ferox lie with the genus Florentinia, differences significantly important enough exist to warrant the formation of a new genus having ferox as the type species. There are several forms in the Late Cretaceous which are similar to S. ferox differing only in detail. For this reason S. ferox has been defined carefully so that morphological variation is limited and specimens
differing only slightly have been placed in S. aff. ferox in this study. Such variations include the presence of a distinctive antapical process, too many processes or the presence of complex processes. A new species, S. buspina, is proposed for specimens with very large complex processes. S. ferox differs from S. tridactylites (Valensi 1955) comb. nov. in possessing a thicker, more granular wall, and having considerably shorter processes.
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Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Florentinia ferox (Deflandre, 1937b) Duxbury, 1980, has basically trifid pre- and postcingular processes, an antapical process that is not distinctive, a thick and densely granular wall, and 3" archeopyle.
Size: overall 78 µm, central body length 46 µm, width 36 µm, processes 15-17 µm.
Originally Hystrichosphaeridium, subsequently Baltisphaeridium, thirdly Hystrichokolpoma, fourthly Silicisphaera, fifthly (and now) Florentinia.
Holotype: Deflandre, 1937, pl.14, figs.3-4
Stratum typicum: Senonian
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Emended descriptions:
as Hystrichokolpoma ferox: Davey, 1969, p. 159:
Diagnosis:
Shell subspherical, densely granular or reticulate.
Processes thin walled, granular, often striated, of three kinds: (i) 6 large precingular and 4 large postcingular, possessing wide bases and tapering distally giving rise to 2 or more tubules, typically open; (ii) a single long tubular antapical process and (iii) cingular and sulcal processes, of moderate length, slender and tubular, only joining proximally if at all.
Archaeopyle apical.
Description:
H. ferox appears to be a fairly variable species. In some specimens the tabulation is not clearly indicated by the processes which tend to be smaller and may even be closed distally. However, the processes usually are well developed, their bases covering an area of the shell surface which is often slightly raised and of the same shape as a thecal plate. The precingular and postcingular processes are largest and give rise distally to as many as 10 tubules. Each cingular process divides proximally into 2 or 3 long slender tubules aligned along the cingulum. The sulcal processes may proximally divide into two tubules or may consist of a single tubule which is sometimes reduced and closed distally. The antapical process is long, tubular, open distally and terminates with a smooth or serrate margin.
Dimensions:
Holotype: length of shell 46 µm, width 36 µm, overall length 78 µm, length of processes 15-17 µm.
Range of Cenomanian specimens: diameter of central body 39(46.1)56 µm, maximum length of processes 27(30.2)36 µm. Number of specimens measured, 13.
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as Silicisphaera ferox: Davey and Verdier, 1976, p. 322-325:
Diagnosis:
The cyst is spherical to subspherical and is thick-walled and densely granular, particularly beneath the processes. The processes are relatively short, weak, and approximately of equal length; they are thin-walled, faintly striate, truncated distally and number one per reflected plate area. The base of each process is broad and covers much of the plate area. There are basically three types of processes: (1) simple, elongate subconical, (2) compound, bifurcating medially; and (3) compound, trifurcating medially. The latter type occupy the pre- and postcingular regions only. The simple and bifurcating processes occupy the apical, cingular, sulcal and antapical regions. The antapical process is not distinctively large.
The archaeopyle is of the combination type: precingular plate 3" is lost and there is a separation of the apical and precingular plates along the plate boundaries, although the apical region typically remains in position, being attached in the ventral region.
Description:
S. ferox comb. nov. is characterized by its relatively thick, granular wall and rather weak, simple, bifurcating and trifurcating processes. A typical example was illustrated by Evitt (1967, pl. 8, figs. 1-5). The cyst wall appears usually to be thicker and more granular beneath the processes giving the impression that the processes are situated on islands between which run the thinner and lower ornamented sutural areas. The simple processes are typical of the genus, being wide proximally, tapering rapidly at first then more gradually; distally they always appear to be truncated. Bifurcation and trifurcation of the larger compound processes take place approximately half way along their length.
Dimensions (in µm):
Holotype:
Central body diameter 36 x 46
Length of processes 15-17
Overall diameter 78
Remarks:
S. ferox and its generic allocation were discussed by Davey and Verdier (1973) who concluded, at that time, that until additional evidence was available no generic reallocation was possible. Now, after considerable further study of this species and of related species it is clear that, although the affinities of ferox lie with the genus Florentinia, differences significantly important enough exist to warrant the formation of a new genus having ferox as the type species. There are several forms in the Late Cretaceous which are similar to S. ferox differing only in detail. For this reason S. ferox has been defined carefully so that morphological variation is limited and specimens
differing only slightly have been placed in S. aff. ferox in this study. Such variations include the presence of a distinctive antapical process, too many processes or the presence of complex processes. A new species, S. buspina, is proposed for specimens with very large complex processes. S. ferox differs from S. tridactylites (Valensi 1955) comb. nov. in possessing a thicker, more granular wall, and having considerably shorter processes.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Florentinia ferox (Deflandre, 1937b) Duxbury, 1980, has basically trifid pre- and postcingular processes, an antapical process that is not distinctive, a thick and densely granular wall, and 3" archeopyle.
Size: overall 78 µm, central body length 46 µm, width 36 µm, processes 15-17 µm.