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Cordosphaeridium robustum
Cordosphaeridium robustum (Gocht, 1969) emend. Sarjeant, 1981
Originally Cordosphaeridium inodes ssp. robustum, subsequently (and now) Cordosphaeridium robustum.
The elevation of this taxon to the species level is not attributable to Islam, 1983.
Lentin and Williams, 1985, did not accept the emendation of this species by Sarjeant, 1981.
Holotype: Gocht, 1969, pl.2, fig.1
Age: Eocene
Translation Gocht, 1969: Sarjeant, 1981, p. 105
Original Diagnosis: Gocht, 1969, p. 42: Cordosphaeridium inodes ssp. robustum
Central body roughly spherical. Processes short, bulky, occasionally slightly conical. Archaeopyle relatively large.
Emended diagnosis: Sarjeant, 1981, p. 105
Cyst spheroidal to broadly ovoidal, two-layered, with surface punctate to shagreenate and sometimes variably ornamented by striae or rugulae. Some 16 processes arise from the periphragm of the complete cyst, probably presenting the paratabulation 4", 6"", 0c, 5""", 0p,1"""". The processes are quite short (in the range one-eighth to one-quarter of the cyst diameter), fibrous and of variable, sometimes considerable, breadth; in profile they may be cylindrical to subconical, tapering or bulbose. They flare distally into a variable number of branches of equally variable relative length, these branches being simple, capitate or very briefly bifurcate.
The antapical process is the largest and most massive, the apical processes the shortest and most slender. Archaeopyle single-plate precingular (type P), relatively large, formed by loss of the third postcingular paraplate: operculum free or loosely attached.
Dimensions: Holotype: length of cyst 66 Ám, breadth 64 Ám, length of processes 8-17 Ám, dimensions of archaeopyle 34 x 32 Ám.
Range of Dimensions. Greatest cyst crossmeasurement 57-74 Ám, length of processes 8-32 Ám.
Affinities: Sarjeant, 1981, p. 106
The morphology of these forms appears sufficiently different from Cordosphaeridium inodes, to justify their elevation to specific status. The processes of C. robustum are much shorter and broader, rarely if ever bifid, and somewhat more consistent in overall structure; the archaeopyle is conspicuously larger.
Originally Cordosphaeridium inodes ssp. robustum, subsequently (and now) Cordosphaeridium robustum.
The elevation of this taxon to the species level is not attributable to Islam, 1983.
Lentin and Williams, 1985, did not accept the emendation of this species by Sarjeant, 1981.
Holotype: Gocht, 1969, pl.2, fig.1
Age: Eocene
Translation Gocht, 1969: Sarjeant, 1981, p. 105
Original Diagnosis: Gocht, 1969, p. 42: Cordosphaeridium inodes ssp. robustum
Central body roughly spherical. Processes short, bulky, occasionally slightly conical. Archaeopyle relatively large.
Emended diagnosis: Sarjeant, 1981, p. 105
Cyst spheroidal to broadly ovoidal, two-layered, with surface punctate to shagreenate and sometimes variably ornamented by striae or rugulae. Some 16 processes arise from the periphragm of the complete cyst, probably presenting the paratabulation 4", 6"", 0c, 5""", 0p,1"""". The processes are quite short (in the range one-eighth to one-quarter of the cyst diameter), fibrous and of variable, sometimes considerable, breadth; in profile they may be cylindrical to subconical, tapering or bulbose. They flare distally into a variable number of branches of equally variable relative length, these branches being simple, capitate or very briefly bifurcate.
The antapical process is the largest and most massive, the apical processes the shortest and most slender. Archaeopyle single-plate precingular (type P), relatively large, formed by loss of the third postcingular paraplate: operculum free or loosely attached.
Dimensions: Holotype: length of cyst 66 Ám, breadth 64 Ám, length of processes 8-17 Ám, dimensions of archaeopyle 34 x 32 Ám.
Range of Dimensions. Greatest cyst crossmeasurement 57-74 Ám, length of processes 8-32 Ám.
Affinities: Sarjeant, 1981, p. 106
The morphology of these forms appears sufficiently different from Cordosphaeridium inodes, to justify their elevation to specific status. The processes of C. robustum are much shorter and broader, rarely if ever bifid, and somewhat more consistent in overall structure; the archaeopyle is conspicuously larger.