Back
Oligosphaeridium totum
Oligosphaeridium totum Brideaux, 1971
Tax. sr. synonym of Oligosphaeridium diastema Singh, 1971, according to Harker and Sarjeant, 1975, and Brideaux and McIntyre, 1975.
Holotype: Brideaux, 1971, pl.25, fig.53
Locus typicus: Alberta, Canada
Stratum typicum: Late Albian
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Oligosphaeridium totum Brideaux, 1971. From Brideaux (1971, p.88), Oligosphaeridium totum has a scabrate wall with biconcave, obconical or nearly tubular processes. The processes have buccinate, entire apices, occasionally with slightly serrate edges and scattered fenestrae,.Size: length of central body (without archeopyle) 36-59 µm, width 29-48 µm, length of processes 12-37 µm, basal width of processes 3-12 µm. This species differs from O.albertense in that the process margins are entire rather than serrate or aculeate. O.totem var minor has smaller processes than O.totum Size: cyst length 26-38 µm, width 17-31 µm, length of processes 4-16 µm, width 1-11 µm.
--------------------------------------------------
Original description (Holotype): Brideaux, 1971, p.88: Oligosphaeridium totum var. totum
Maximum width, 42 µm; 14 processes present corresponding to a tabulation scheme of 6", 0c, 5''', 1p, 1'''', 1s; columns of processes wider basally, narrowing medially, and flaring at their apices; processes open, margins entire, buccinate, edges sometimes irregular, a few fenestrae present; processes 21-36 µm long and 3-9 µm wide basally. Archeopyle apical, margin irregular. Thin two-layered wall, scabrate.
Description: Brideaux, 1971, p.88: Oligosphaeridium totum var. totum
Cyst outline in lateral view subcircular, in apical view circular or subcircular. Wall thin, scabrate, two-layered, the outer layer giving rise to biconcave, obconical or nearly tubular processes; the processes with buccinate, entire apices, occasionally with slightly serrate edges and scattered fenestrae; open apically, hollow, and with bases expanding slightly at the junction of cyst wall and processes. Numerous complete specimens bear no more than 18 processes; those bearing a polygonal apical archeopyle often bear 14 processes, one process appearing smaller, probably corresponding to a sulcul process. Arrangement of processes on suitably oriented specimens appears to correspond to a reflected tabulation scheme of 4', 6", 0c, 5-?6", 1p. 1'''', ?1s.
Dimensions: Length of 30 measured specimens (with and without archeopyle), 36--59 µm; width on 21 measured specimens, 29--48 µm; length of processes, 12--37 Ám; basal width of processes, 3--12 µm. Total of 52 specimens recorded.
Remarks: A number of specimens possess only 8 or 9 processes. It is suggested that the remaining processes were lost as a result of mechanical breakage either during fossilization or during the maceration process. Such an interpretation is supported by the occasional occurrence of specimens bearing rounded breaks in the cyst wall which correspond in position to normal emplacement of processes.
Affinities:
Brideaux, 1971, p.88: Oligosphaeridium totum var. totum is distinguished by its relatively large, biconcave, buccinate, entire-margined processes. Oligosphaeridium albertense has irregular processes which are larger and which have serrate or aculeate margins.
Tax. sr. synonym of Oligosphaeridium diastema Singh, 1971, according to Harker and Sarjeant, 1975, and Brideaux and McIntyre, 1975.
Holotype: Brideaux, 1971, pl.25, fig.53
Locus typicus: Alberta, Canada
Stratum typicum: Late Albian
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Oligosphaeridium totum Brideaux, 1971. From Brideaux (1971, p.88), Oligosphaeridium totum has a scabrate wall with biconcave, obconical or nearly tubular processes. The processes have buccinate, entire apices, occasionally with slightly serrate edges and scattered fenestrae,.Size: length of central body (without archeopyle) 36-59 µm, width 29-48 µm, length of processes 12-37 µm, basal width of processes 3-12 µm. This species differs from O.albertense in that the process margins are entire rather than serrate or aculeate. O.totem var minor has smaller processes than O.totum Size: cyst length 26-38 µm, width 17-31 µm, length of processes 4-16 µm, width 1-11 µm.
--------------------------------------------------
Original description (Holotype): Brideaux, 1971, p.88: Oligosphaeridium totum var. totum
Maximum width, 42 µm; 14 processes present corresponding to a tabulation scheme of 6", 0c, 5''', 1p, 1'''', 1s; columns of processes wider basally, narrowing medially, and flaring at their apices; processes open, margins entire, buccinate, edges sometimes irregular, a few fenestrae present; processes 21-36 µm long and 3-9 µm wide basally. Archeopyle apical, margin irregular. Thin two-layered wall, scabrate.
Description: Brideaux, 1971, p.88: Oligosphaeridium totum var. totum
Cyst outline in lateral view subcircular, in apical view circular or subcircular. Wall thin, scabrate, two-layered, the outer layer giving rise to biconcave, obconical or nearly tubular processes; the processes with buccinate, entire apices, occasionally with slightly serrate edges and scattered fenestrae; open apically, hollow, and with bases expanding slightly at the junction of cyst wall and processes. Numerous complete specimens bear no more than 18 processes; those bearing a polygonal apical archeopyle often bear 14 processes, one process appearing smaller, probably corresponding to a sulcul process. Arrangement of processes on suitably oriented specimens appears to correspond to a reflected tabulation scheme of 4', 6", 0c, 5-?6", 1p. 1'''', ?1s.
Dimensions: Length of 30 measured specimens (with and without archeopyle), 36--59 µm; width on 21 measured specimens, 29--48 µm; length of processes, 12--37 Ám; basal width of processes, 3--12 µm. Total of 52 specimens recorded.
Remarks: A number of specimens possess only 8 or 9 processes. It is suggested that the remaining processes were lost as a result of mechanical breakage either during fossilization or during the maceration process. Such an interpretation is supported by the occasional occurrence of specimens bearing rounded breaks in the cyst wall which correspond in position to normal emplacement of processes.
Affinities:
Brideaux, 1971, p.88: Oligosphaeridium totum var. totum is distinguished by its relatively large, biconcave, buccinate, entire-margined processes. Oligosphaeridium albertense has irregular processes which are larger and which have serrate or aculeate margins.