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Operculodinium oriensum
Operculodinium oriensum Warny et Wrenn 1997
Holotype: Warny et Wrenn 1997: Plate I, 7-9
Type locality: Bou Regreg S Core, Sale, Riffian Corridor, Morocco.
Stratum typicum: Messinian
Stratigraphic range: Tortonian-Messinian/Upper Miocene, samples B102 (171.35 m) S22 (23.74 m) (Fig. 2).
Original diagnosis: Warny et Wrenn 1997, p. 290-291
A species of Operculodinium with short, commonly perforate processes that bear aligned sculptural elements (granules or ridges). The processes taper distally from a broad base and exhibit a variety of terminations (e.g., acicular, flat, rounded, bifurcate, etc.). The cyst surface is micropunctate or granulate.
Description: Warny et Wrenn 1997, p. 290-291
Shape: Spherical chorate cyst. Processes: The short processes are variably shaped, often perforate and bear aligned sculptural elements (granules or ridges) that lend a striate aspect to them. They taper distally from a broad base and exhibit a variety of terminations (e.g., acicular, flat, rounded, bifurcate, etc). Typically there are 80 to 100 processes per cyst; approximately 18 processes appear around the cyst margin when viewed in optical section. Phragma: The cyst is composed of two closely appressed walls whose combined thickness is about 2 llm. The surface of the cyst is microgranulate or micropunctate. Archeopyle: The archeopyle is precingular Type P (3"only). Paratabulation, paracingulum and parasulcus: Not evident.
Dimensions: Holotype: Diameter of cyst 34 Ám; length of process 10.2 Ám. Mean (x) and extreme values for n= 10: diameter of cyst 31-(35) 37Ám; length of process 4 (6)-10 Ám.
Comparisons: Warny et Wrenn 1997, p. 290-291: Operculodinium oriensum differs from O. israelianum and O. crassum by having a smaller overall diameter, smaller central body diameter and fewer processes that are commonly perforate and much broader proximally. In addition, the processes of O. oriensum have granules or ridges running along their length, giving it a striate appearance, which is not found in specimens of O. crassum and O. israelianum. In contrast, the processes of O. israelianum are fibrous and may be perforate, but only proximally. Furthermore, the ratio of cyst diameter to process length is about 6 for O. oriensum compared to 8 for O. israelianum.
Comments: Warny et Wrenn 1997, p. 290-291: O. oriensum is abundant in the Miocene, decreases just below the Mio-Pliocene boundary and disappears in the Early Pliocene.
Holotype: Warny et Wrenn 1997: Plate I, 7-9
Type locality: Bou Regreg S Core, Sale, Riffian Corridor, Morocco.
Stratum typicum: Messinian
Stratigraphic range: Tortonian-Messinian/Upper Miocene, samples B102 (171.35 m) S22 (23.74 m) (Fig. 2).
Original diagnosis: Warny et Wrenn 1997, p. 290-291
A species of Operculodinium with short, commonly perforate processes that bear aligned sculptural elements (granules or ridges). The processes taper distally from a broad base and exhibit a variety of terminations (e.g., acicular, flat, rounded, bifurcate, etc.). The cyst surface is micropunctate or granulate.
Description: Warny et Wrenn 1997, p. 290-291
Shape: Spherical chorate cyst. Processes: The short processes are variably shaped, often perforate and bear aligned sculptural elements (granules or ridges) that lend a striate aspect to them. They taper distally from a broad base and exhibit a variety of terminations (e.g., acicular, flat, rounded, bifurcate, etc). Typically there are 80 to 100 processes per cyst; approximately 18 processes appear around the cyst margin when viewed in optical section. Phragma: The cyst is composed of two closely appressed walls whose combined thickness is about 2 llm. The surface of the cyst is microgranulate or micropunctate. Archeopyle: The archeopyle is precingular Type P (3"only). Paratabulation, paracingulum and parasulcus: Not evident.
Dimensions: Holotype: Diameter of cyst 34 Ám; length of process 10.2 Ám. Mean (x) and extreme values for n= 10: diameter of cyst 31-(35) 37Ám; length of process 4 (6)-10 Ám.
Comparisons: Warny et Wrenn 1997, p. 290-291: Operculodinium oriensum differs from O. israelianum and O. crassum by having a smaller overall diameter, smaller central body diameter and fewer processes that are commonly perforate and much broader proximally. In addition, the processes of O. oriensum have granules or ridges running along their length, giving it a striate appearance, which is not found in specimens of O. crassum and O. israelianum. In contrast, the processes of O. israelianum are fibrous and may be perforate, but only proximally. Furthermore, the ratio of cyst diameter to process length is about 6 for O. oriensum compared to 8 for O. israelianum.
Comments: Warny et Wrenn 1997, p. 290-291: O. oriensum is abundant in the Miocene, decreases just below the Mio-Pliocene boundary and disappears in the Early Pliocene.