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Tanyosphaeridium magdalium
Tanyosphaeridium magdalium (Drugg, 1967) Heisecke, 1970
Originally Hystrichosphaeridium, subsequently Tanyosphaeridium.
Taxonomic senior synonym: Hystrichosphaera (as and now Tanyosphaeridium) xanthiopyxides, according to Stover and Evitt (1978, p.85).
Holotype: Drugg, 1967, pl.4, fig.9
Paratype: Drugg, 1967
Locus typicus: Escarpado Canyan, California
Stratum typicum: Danian
Original diagnosis: Drugg, 1967, p.26-27: Hystrichosphaeridium magdalium
Test cylindrical with rounded ends, wall thin and granulate. The test opens by means of an apical archeopyle, the line of separation being zigzag (see pl. 9, fig. 7). Test covered with long, delicate, hollow processes. The distal ends are slightly flared and presumably open, although the diminutive size renders verification of this point difficult. The processes are usually distributed equally over the surface of the test. Some specimens, however, exhibit a naked equatorial area (see pl. 4, fig. 10) which is often more densely granulate than the rest of the test. This naked area is probably analogous to a girdle structure. Examples expressing such naked regions have not been separated out as a separate species because of the existence of intermediate forms. Test dimensions: Holotype 25 x 30 µm; range 17 to 29 µm. wide, 22 to 36 µm long; processes about 1 µm long.
Affinities:
Drugg, 1967, p.27: Hystrichosphaeridium magdalium
This species is similar to several previously described elongate forms. It differs from Baltisphaeridium granulosum (Deflandre) Sarjeant 1962 in that it does not have pointed processes. From Hystrichosphaeridium isocalamus Deflandre and Cookson 1955 it differs in that the test is granulate and the processes are flared distally. It differs from Baltisphaeridium mixtispinosum Kement 1960 in that it lacks two different kinds of processes. It is perhaps closest to Hystrichosphaeridium capitatum Cookson and Eisenack 1960 from which it differs in possessing processes which are much longer in relation to the size of the test.
Originally Hystrichosphaeridium, subsequently Tanyosphaeridium.
Taxonomic senior synonym: Hystrichosphaera (as and now Tanyosphaeridium) xanthiopyxides, according to Stover and Evitt (1978, p.85).
Holotype: Drugg, 1967, pl.4, fig.9
Paratype: Drugg, 1967
Locus typicus: Escarpado Canyan, California
Stratum typicum: Danian
Original diagnosis: Drugg, 1967, p.26-27: Hystrichosphaeridium magdalium
Test cylindrical with rounded ends, wall thin and granulate. The test opens by means of an apical archeopyle, the line of separation being zigzag (see pl. 9, fig. 7). Test covered with long, delicate, hollow processes. The distal ends are slightly flared and presumably open, although the diminutive size renders verification of this point difficult. The processes are usually distributed equally over the surface of the test. Some specimens, however, exhibit a naked equatorial area (see pl. 4, fig. 10) which is often more densely granulate than the rest of the test. This naked area is probably analogous to a girdle structure. Examples expressing such naked regions have not been separated out as a separate species because of the existence of intermediate forms. Test dimensions: Holotype 25 x 30 µm; range 17 to 29 µm. wide, 22 to 36 µm long; processes about 1 µm long.
Affinities:
Drugg, 1967, p.27: Hystrichosphaeridium magdalium
This species is similar to several previously described elongate forms. It differs from Baltisphaeridium granulosum (Deflandre) Sarjeant 1962 in that it does not have pointed processes. From Hystrichosphaeridium isocalamus Deflandre and Cookson 1955 it differs in that the test is granulate and the processes are flared distally. It differs from Baltisphaeridium mixtispinosum Kement 1960 in that it lacks two different kinds of processes. It is perhaps closest to Hystrichosphaeridium capitatum Cookson and Eisenack 1960 from which it differs in possessing processes which are much longer in relation to the size of the test.