Back
Operculodinium alsium
Operculodinium alsium Matsuoka and Bujak, 1988
Holotype: Matsuoka and Bujak, 1988, pl.8, fig.8a-b
Paratype: Matsuoka and Bujak, 1988
Locus typicus: Norton Sound COST No. 1 Well, Norton Sound, Bering Sea
Stratum typicum: Hystrichosphaeropsis variabile Zone: Late Miocene
Original diagnosis: Matsuoka and Bujak, 1988, p.64
Intermediate subspherical to ovoidal proximochorate cyst. Cyst wall comprising a reticulate periphragm and a smooth endophragm adpressed between processes. Processes numerous, short, hollow, cylindrical to sometimes conical, apparently nontabular with closed and sometimes truncated distal extremities. Processes reticulate at the base. No features except for archeopyle sutures reflect the paratabulation. Archeopyle precingular, formed by the loss of paraplate 3".
Description: Matsuoka and Bujak, 1988, p.65
The subsphercal to ovoidal cyst possesses a thick reticulate periphragm and a relatively thin smooth endophragm. Many of the processes are cylindrical with truncated distal endings, but some are short, conical and a few adjacent processes are rarely joined. The archeopyle is trapezoidal, precingular and formed by the loss of paraplate 3".
Dimensions: Holotype; cyst diameter 55 x 62 Ám, length of processes up to 7 Ám, Range; cyst diameter 47-62 Ám, length of processes 5-7 Ám. Number of specimens measured; 5.
Thecal affinities: Possibly related to the modern genus Protoceratium of the Gonyaulacaceae.
Affinities:
Matsuoka and Bujak, 1988, p.65: The short cylindrical processes with truncated distal extremities and the relatively thick and reticulate periphragm distinguish Operculodinium alsium from other species of Operculodinium. Operculodinium sp. I recorded by Manum (1976, pl. 1, fig. 23-24) from upper Eocene sediments of the Norwegian-Greenland Sea may be conspecific with O. alsium because it apparently has a reticulate periphragm and short cylindrical processes.
Holotype: Matsuoka and Bujak, 1988, pl.8, fig.8a-b
Paratype: Matsuoka and Bujak, 1988
Locus typicus: Norton Sound COST No. 1 Well, Norton Sound, Bering Sea
Stratum typicum: Hystrichosphaeropsis variabile Zone: Late Miocene
Original diagnosis: Matsuoka and Bujak, 1988, p.64
Intermediate subspherical to ovoidal proximochorate cyst. Cyst wall comprising a reticulate periphragm and a smooth endophragm adpressed between processes. Processes numerous, short, hollow, cylindrical to sometimes conical, apparently nontabular with closed and sometimes truncated distal extremities. Processes reticulate at the base. No features except for archeopyle sutures reflect the paratabulation. Archeopyle precingular, formed by the loss of paraplate 3".
Description: Matsuoka and Bujak, 1988, p.65
The subsphercal to ovoidal cyst possesses a thick reticulate periphragm and a relatively thin smooth endophragm. Many of the processes are cylindrical with truncated distal endings, but some are short, conical and a few adjacent processes are rarely joined. The archeopyle is trapezoidal, precingular and formed by the loss of paraplate 3".
Dimensions: Holotype; cyst diameter 55 x 62 Ám, length of processes up to 7 Ám, Range; cyst diameter 47-62 Ám, length of processes 5-7 Ám. Number of specimens measured; 5.
Thecal affinities: Possibly related to the modern genus Protoceratium of the Gonyaulacaceae.
Affinities:
Matsuoka and Bujak, 1988, p.65: The short cylindrical processes with truncated distal extremities and the relatively thick and reticulate periphragm distinguish Operculodinium alsium from other species of Operculodinium. Operculodinium sp. I recorded by Manum (1976, pl. 1, fig. 23-24) from upper Eocene sediments of the Norwegian-Greenland Sea may be conspecific with O. alsium because it apparently has a reticulate periphragm and short cylindrical processes.