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Operculodinium corradinii
Operculodinium corradinii Slimani, 1994, p.80–81, pl.12, figs.20–23. Holotype: Slimani, 1994, pl.12, figs.22–23. Age: early Campanian–early Maastrichtian.
Original description (Slimani, 1994):
Operculodinium corradinii sp. nov. (Pl. 12, Fig. 20-23)
Name derivation: In honor of Domenico CORRADINI, who worked on biostratigraphy and dinoflagellates of the Upper Cretaceous, Institute of Paleontology, University of Modena, Italy.
Holocaust: Turnhout -933 m, preparation 8, E.F. coord. U42.
Type locality: Turnhout -933 m.
Type horizon: Campanian.
Synonymy:
?1973: Operculodinium cf. polytrichum (VALENSI) - CORRADINI, p. 157-158, pl. 23, fig. 8.
?1973: Operculodinium sp. - CORRADINI. p. 158; pl. 23; fig. 4. 7a, b; pl. 34. fig. 4.
Diagnosis: Chorate cyst lacking distinct apical and antapical processes. The central body is spheroidal to subspheroidal, fibrous, and bears numerous intratabular processes, between 1/3 and 1/2 of its diameter in height. They are solid, often fibrous, and converge at their base; they are simple or bifurcated to trifurcated and terminate distally in a capitate end. The archaeopyle is precingulate of type P(3") with a free operculum or recovered inside the cyst.
Dimensions: Holotype. Maximum diameter of the central body: 46 µm, total diameter: 80 µm. Variations: Maximum diameter of the central body: 30-50 µm, total diameter: 50-80 µm. Process length: 10-20 µm. Number of specimens measured: 20.
Material: > 150 specimens.
Description: The smooth endophragm and the fibrous periphragm are in close contact and form a single wall about 2 µm thick. The processes are uniformly distributed, converge at their base, then gradually taper towards their distal end; they terminate distally in a capitate end with a slightly truncated apex. The proportion of furcate processes varies from a few to 1/3 of the total number of processes. There is an occasional alignment of processes on the paracingulum or sometimes even on the epicyst. The length of the processes is uniform in the same individual but varies intraspecifically.
Note: Operculodinium corradinii sp. nov. is distinguished from other species of the genus Operculodinium by its proximally confluent and distally capitate processes, and especially by the presence of bifurcated and trifurcated processes. It is probably comparable to the Upper Cretaceous forms of Italy, which are listed by CORRADINI (1973) under the names Operculodinium sp. and Operculodinium cf. pobitrichum (see synonymy above). The type and nature of the processes of this species are reminiscent of Amphorosphaeridium fenestratum subsp. dividum DAVEY (1969C), with which it is associated in the material studied, but it differs largely in the absence of distinct apical and antapical processes.
Locality: Turnhout: -987 to -850.72 m, Lower Campanian - Lower Maastrichtian
Original description (Slimani, 1994):
Operculodinium corradinii sp. nov. (Pl. 12, Fig. 20-23)
Name derivation: In honor of Domenico CORRADINI, who worked on biostratigraphy and dinoflagellates of the Upper Cretaceous, Institute of Paleontology, University of Modena, Italy.
Holocaust: Turnhout -933 m, preparation 8, E.F. coord. U42.
Type locality: Turnhout -933 m.
Type horizon: Campanian.
Synonymy:
?1973: Operculodinium cf. polytrichum (VALENSI) - CORRADINI, p. 157-158, pl. 23, fig. 8.
?1973: Operculodinium sp. - CORRADINI. p. 158; pl. 23; fig. 4. 7a, b; pl. 34. fig. 4.
Diagnosis: Chorate cyst lacking distinct apical and antapical processes. The central body is spheroidal to subspheroidal, fibrous, and bears numerous intratabular processes, between 1/3 and 1/2 of its diameter in height. They are solid, often fibrous, and converge at their base; they are simple or bifurcated to trifurcated and terminate distally in a capitate end. The archaeopyle is precingulate of type P(3") with a free operculum or recovered inside the cyst.
Dimensions: Holotype. Maximum diameter of the central body: 46 µm, total diameter: 80 µm. Variations: Maximum diameter of the central body: 30-50 µm, total diameter: 50-80 µm. Process length: 10-20 µm. Number of specimens measured: 20.
Material: > 150 specimens.
Description: The smooth endophragm and the fibrous periphragm are in close contact and form a single wall about 2 µm thick. The processes are uniformly distributed, converge at their base, then gradually taper towards their distal end; they terminate distally in a capitate end with a slightly truncated apex. The proportion of furcate processes varies from a few to 1/3 of the total number of processes. There is an occasional alignment of processes on the paracingulum or sometimes even on the epicyst. The length of the processes is uniform in the same individual but varies intraspecifically.
Note: Operculodinium corradinii sp. nov. is distinguished from other species of the genus Operculodinium by its proximally confluent and distally capitate processes, and especially by the presence of bifurcated and trifurcated processes. It is probably comparable to the Upper Cretaceous forms of Italy, which are listed by CORRADINI (1973) under the names Operculodinium sp. and Operculodinium cf. pobitrichum (see synonymy above). The type and nature of the processes of this species are reminiscent of Amphorosphaeridium fenestratum subsp. dividum DAVEY (1969C), with which it is associated in the material studied, but it differs largely in the absence of distinct apical and antapical processes.
Locality: Turnhout: -987 to -850.72 m, Lower Campanian - Lower Maastrichtian