Back
Operculodinium variabile
Operculodinium variabile Zevenboom and Santarelli in Zevenboom, 1995, p.140–141, pl.7, figs.7–12.
Name not validly published: considered a manuscript name.
Holotype: Zevenboom, 1995, pl.7, figs.7–9.
Age: early–late Miocene.
----------------------------------------------
Original dscription (Zevenboom, 1995)
Operculodinium variabile Zevenboom and Santarelli sp.nov. (manuscript name) (Plate VII, 9-11, 13-15).
1986c Operculodinium sp. B, Powell, plate 5, fig. 2
1993 Operculodinium sp. C, Martin, fig. 13 C-F
Manuscript holotype: Sample, CP 3668/1, EF (F31), Plate VII 7-9.
Manuscript paratype: sample CP 3651/1, EF (E45), Plate VII, 10-12
Etymology: In references to the variable morphology of the processes
Type locality: Giammoia section Sicily, Italy
Type stratum: Middle Miocene
Diagnosis: A subspherical species of Operculodinium characterized by the variable size and morphology of the short hollow processes.
Dimensions: Height 25 (27) 30 µm, Width 28 (30) 33 µm (excluding processes). Processes 4 (5) 6 µm. Wall thickness 2-3 µm. N = 25
Description: A subspherical speices of Operculodinium. Endo- and periphargm are closely appressed. The periphragm is faintly microgranulate. Processes are highly variable in shape on one specimen and are mostly distally open. The processes are small, hollow, buccinate, cylindrical or elongate subconical in shape and regularly distributed over the cyst body and show no apparent paratabulation. The archeopyle is formed by the loss of paraplate 3’’. The archeopyle margin is serrate.
Discussion: Operculodinium variabile is morphologically similar to Operculodinium piaseckii Zevenboom and Santarelli sp. nov. and Operculodinium janduchenei Head, 1989c, but differs is possessing more than one type of process. It differs from the also morphologically similar Pyxidinopsis tuberculate Versteegh and Zevenboom, 1995, in having clearly developed isolated processes rather than processes connected by ridges.
Occurrences: Italy (Powell, 1986c and this study), The Netherlands (this study)
Total stratigraphic range: early Miocene to Late Miocene (this study) see Fig. 5
----------------------------------------------
Name not validly published: considered a manuscript name.
Holotype: Zevenboom, 1995, pl.7, figs.7–9.
Age: early–late Miocene.
----------------------------------------------
Original dscription (Zevenboom, 1995)
Operculodinium variabile Zevenboom and Santarelli sp.nov. (manuscript name) (Plate VII, 9-11, 13-15).
1986c Operculodinium sp. B, Powell, plate 5, fig. 2
1993 Operculodinium sp. C, Martin, fig. 13 C-F
Manuscript holotype: Sample, CP 3668/1, EF (F31), Plate VII 7-9.
Manuscript paratype: sample CP 3651/1, EF (E45), Plate VII, 10-12
Etymology: In references to the variable morphology of the processes
Type locality: Giammoia section Sicily, Italy
Type stratum: Middle Miocene
Diagnosis: A subspherical species of Operculodinium characterized by the variable size and morphology of the short hollow processes.
Dimensions: Height 25 (27) 30 µm, Width 28 (30) 33 µm (excluding processes). Processes 4 (5) 6 µm. Wall thickness 2-3 µm. N = 25
Description: A subspherical speices of Operculodinium. Endo- and periphargm are closely appressed. The periphragm is faintly microgranulate. Processes are highly variable in shape on one specimen and are mostly distally open. The processes are small, hollow, buccinate, cylindrical or elongate subconical in shape and regularly distributed over the cyst body and show no apparent paratabulation. The archeopyle is formed by the loss of paraplate 3’’. The archeopyle margin is serrate.
Discussion: Operculodinium variabile is morphologically similar to Operculodinium piaseckii Zevenboom and Santarelli sp. nov. and Operculodinium janduchenei Head, 1989c, but differs is possessing more than one type of process. It differs from the also morphologically similar Pyxidinopsis tuberculate Versteegh and Zevenboom, 1995, in having clearly developed isolated processes rather than processes connected by ridges.
Occurrences: Italy (Powell, 1986c and this study), The Netherlands (this study)
Total stratigraphic range: early Miocene to Late Miocene (this study) see Fig. 5
----------------------------------------------