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Operculodinium centrocarpum var. cezare
From Fensome et al., 2019:
Operculodinium centrocarpum var. cezare de Vernal et al., 1989, p.2462, pl.1, figs.8–11 ex Head, 2007, p.1011. Holotype: de Vernal et al., 1989, pl.1, figs.8–9; de Vernal et al., 2001, fig.3.4 (lower panel); designated by Head (2007, p.1011). The name was not validly published in de Vernal et al. (1989), since these authors did not designate a holotype. Age: Quaternary.
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Original description (de vernal et al., 1989):
Operculodinium centrocarpum var. cezare (pl. 1, fig. 8-11)
Justification of the name: The variety name cezare is proposed in reference to the Saint-Césaire site.
Description: The cysts attributed to O. centrocarpum var. cezare are spherical to subspherical and possess a large, trapezoidal precingulate archaeopyle. They are characterized by a cyst diameter comparable to that of O. centrocarpum, averaging 45 µm (41-49 µm, N = 12). The cyst membrane is thin (0.5–1.0 µm) and ornamented with densely and irregularly distributed microgranules. Operculodinium centrocarpum var. cezare is distinguished by the extreme reduction of non-tabular processes, consisting for the most part, if not all, of thin echinules or radial fibers whose length generally varies between 1.5 and 2.0 µm, rarely reaching 3.0 µm. Some specimens bear a few isolated processes whose structure is similar to those that usually characterize O. centrocarpum. These processes, which are conical, hollow and finely striated at the base, have a multifurcate termination.
Remarks: The cysts described above are attributed to O. centrocarpum because of the morphological intergradations that some processes of intermediate forms present. The extreme forms, exclusively equipped with short radial fibers, could not otherwise be associated with the species O. centrocarpum. The variety cezare could have resulted from the encystment of gonyaulax grindleyi under particular physicochemical conditions, characterized by low salinities for example. The encystment of marine dinoflagellates in polyhaline environments seems in fact to be accompanied by a reduction in the dimensions of the processes for many taxa (Dale 1988).
Operculodinium centrocarpum var. cezare de Vernal et al., 1989, p.2462, pl.1, figs.8–11 ex Head, 2007, p.1011. Holotype: de Vernal et al., 1989, pl.1, figs.8–9; de Vernal et al., 2001, fig.3.4 (lower panel); designated by Head (2007, p.1011). The name was not validly published in de Vernal et al. (1989), since these authors did not designate a holotype. Age: Quaternary.
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Original description (de vernal et al., 1989):
Operculodinium centrocarpum var. cezare (pl. 1, fig. 8-11)
Justification of the name: The variety name cezare is proposed in reference to the Saint-Césaire site.
Description: The cysts attributed to O. centrocarpum var. cezare are spherical to subspherical and possess a large, trapezoidal precingulate archaeopyle. They are characterized by a cyst diameter comparable to that of O. centrocarpum, averaging 45 µm (41-49 µm, N = 12). The cyst membrane is thin (0.5–1.0 µm) and ornamented with densely and irregularly distributed microgranules. Operculodinium centrocarpum var. cezare is distinguished by the extreme reduction of non-tabular processes, consisting for the most part, if not all, of thin echinules or radial fibers whose length generally varies between 1.5 and 2.0 µm, rarely reaching 3.0 µm. Some specimens bear a few isolated processes whose structure is similar to those that usually characterize O. centrocarpum. These processes, which are conical, hollow and finely striated at the base, have a multifurcate termination.
Remarks: The cysts described above are attributed to O. centrocarpum because of the morphological intergradations that some processes of intermediate forms present. The extreme forms, exclusively equipped with short radial fibers, could not otherwise be associated with the species O. centrocarpum. The variety cezare could have resulted from the encystment of gonyaulax grindleyi under particular physicochemical conditions, characterized by low salinities for example. The encystment of marine dinoflagellates in polyhaline environments seems in fact to be accompanied by a reduction in the dimensions of the processes for many taxa (Dale 1988).