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Nematosphaeropsis elegantula
Nematosphaeropsis elegantula (Drugg, 1967) Stover and Williams, 1987
Now Trabeculidium. Originally Cannosphaeropsis, subsequently (and now) Trabeculidium, thirdly Nematosphaeropsis.
Lentin and Williams, 1993, retained this species in Trabeculidium Duxbury, 1980, following Sarjeant, 1989, who maintained that Trabeculidium is a separate genus.
Jan du Chêne, 1988, also effected this transfer.
Holotype: Drugg, 1967, pl.4, fig.17
Locus typicus: Escarpado Canyon, California, U.S.A.
Stratum typicum: Danian
Original diagnosis: Drugg, 1967, p.24: Cannosphaeropsis elegantula
Test small, more or less oval, covered with about 15 to 20 processes supporting an external network of fine threads. The wall is thin and devoid of visible structure. The processes are about 14 Ám in length and branch at the tips into 4 or 5 branches which may branch again. At times one or two of the processes on one pole may be broader than the rest suggesting some sort of symmetry. The interconnecting filaments are fine and sometimes bear a few tiny beads or barbs. A noticeable feature of these threads is that they tend to project in fairly straight lines between the processes and that they tend to occur in pairs as parallel strands. The overall pattern formed by these parallel interconnections is vaguely reminiscent of the polygonal fields of Hystrichosphaera. This pattern is limited only to the interconnections at the process tips, there being no equivalent ridges or interconnections at the bases of the processes.
Dimensions: Holotype, body 37x53 Ám, overall 61x72 Ám; range of test size 28-37 Ám wide, 33-53 Ám long.
Affinities:
Drugg, 1967, p.25: Cannosphaeropsis elegantula
This species bears a general resemblance to Cannosphaeropsis tutulosa Cookson and Eisenack 1960. It differs most noticeably in the absence of the outloops of C. tutulosa and in the possession of the parallel threads described above.
Now Trabeculidium. Originally Cannosphaeropsis, subsequently (and now) Trabeculidium, thirdly Nematosphaeropsis.
Lentin and Williams, 1993, retained this species in Trabeculidium Duxbury, 1980, following Sarjeant, 1989, who maintained that Trabeculidium is a separate genus.
Jan du Chêne, 1988, also effected this transfer.
Holotype: Drugg, 1967, pl.4, fig.17
Locus typicus: Escarpado Canyon, California, U.S.A.
Stratum typicum: Danian
Original diagnosis: Drugg, 1967, p.24: Cannosphaeropsis elegantula
Test small, more or less oval, covered with about 15 to 20 processes supporting an external network of fine threads. The wall is thin and devoid of visible structure. The processes are about 14 Ám in length and branch at the tips into 4 or 5 branches which may branch again. At times one or two of the processes on one pole may be broader than the rest suggesting some sort of symmetry. The interconnecting filaments are fine and sometimes bear a few tiny beads or barbs. A noticeable feature of these threads is that they tend to project in fairly straight lines between the processes and that they tend to occur in pairs as parallel strands. The overall pattern formed by these parallel interconnections is vaguely reminiscent of the polygonal fields of Hystrichosphaera. This pattern is limited only to the interconnections at the process tips, there being no equivalent ridges or interconnections at the bases of the processes.
Dimensions: Holotype, body 37x53 Ám, overall 61x72 Ám; range of test size 28-37 Ám wide, 33-53 Ám long.
Affinities:
Drugg, 1967, p.25: Cannosphaeropsis elegantula
This species bears a general resemblance to Cannosphaeropsis tutulosa Cookson and Eisenack 1960. It differs most noticeably in the absence of the outloops of C. tutulosa and in the possession of the parallel threads described above.