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Oligosphaeridium anthophorum
Oligosphaeridium anthophorum (Cookson and Eisenack, 1958) Davey, 1969
Now Stiphrosphaeridium. Originally Hystrichosphaeridium, subsequently Oligosphaeridium, thirdly Polystephanephorus, fourthly Hystrichosphaerina, fifthly (and now) Stiphrosphaeridium.
Tax. sr. synonym of Hystrichosphaerina schindewolfii Alberti, 1961, according to Davey, 1979. Lentin and Williams, 1981, retained Hystrichosphaerina schindewolfii as a separate species.
Davey, 1979, transferred this species to Polystephanephorus Sarjeant, 1961. Duxbury, 1980, transferred the species to Hystrichosphaerina Alberti, 1961. Lentin and Williams, 1981, retained it in Oligosphaeridium.
This combination was not validly published in Davey and Williams, 1966, since these authors did not fully reference the basionym.
Holotype: Cookson and Eisenack, 1958, pl.11, fig.12
Locus typicus: Omatia, Papua
Stratum typicum: Aptian-Albian
Original description: Cookson and Eisenack, 1958, p.43: Hystrichosphaeridium anthophorum
Shell sphaeroidal and provided with about 10-15 stalked tabular appendages. The stalks of the appendages which are short and sometimes broad, and frequently show the longitudinal fibrils of which they are composed, gradually widen distally, frequently close to the shell, in deep broad terminal expansions with completely and irregularly reticulate walls and continuous smooth or finely serrated outer edges.
Dimensions: Holotype: Shell 70 µm, overall 210 µm; appandages c. 50 µm.
Supplemental description: Davey, 1969, p.147
The shell is subspherical; shell wall smooth to lightly granular. An apical archaeopyle is typically developed and possesses an angular margin. The processes are hollow, buccinate to infundibular, with the distal flared portion perforate. Distally the margins of the processes are usually entire, but may bear one or two small spines. A complete specimen possesses 18 processes, reflecting a tabulation characteristic of this genus. The processes are all of equal size except for the first postcingular (1""") and the posterior intercalary (1p) which are often reduced.
Dimensions: Range of observed specimens: diameter of central body 38(46.3)57 µm, maximum length of processes 18(34.1)43 µm. Number of specimens measured, 8.
Affinities:
Cookson and Eisenack, 1958, p.43-44: Hystrichosphaeridium anthophorum
Hystrichosphaeridium anthophorum is morphologically close to H. pulcherrimum Deflandre and Cookson and H. dictyoplocus Klumpp. It differs from H. pulcherrimum in the more extensive reticulation of the appendages and the entire edge of the terminal expansion, and from H. dictyoplocus in the shorter and somewhat broader appandages and the wider mesh and continuous margin of the terminal expansions.
Brideaux, 1971, p.89: Oligosphaeridium anthophorum is characterized by flaring fenestrate or foveolate processes with entire open margins. The closely related form, O. pulcherrimum (Deflandre and Cookson) Davey and Williams 1966 possesses flaring fenestrate processes but without entire apices. O. dictyophorum (Deflandre and Cookson) Davey and Williams 1969, p.5 appears to differ from these two species in having thin, solid-walled columns and wide-meshed, strongly expanded columns.
Now Stiphrosphaeridium. Originally Hystrichosphaeridium, subsequently Oligosphaeridium, thirdly Polystephanephorus, fourthly Hystrichosphaerina, fifthly (and now) Stiphrosphaeridium.
Tax. sr. synonym of Hystrichosphaerina schindewolfii Alberti, 1961, according to Davey, 1979. Lentin and Williams, 1981, retained Hystrichosphaerina schindewolfii as a separate species.
Davey, 1979, transferred this species to Polystephanephorus Sarjeant, 1961. Duxbury, 1980, transferred the species to Hystrichosphaerina Alberti, 1961. Lentin and Williams, 1981, retained it in Oligosphaeridium.
This combination was not validly published in Davey and Williams, 1966, since these authors did not fully reference the basionym.
Holotype: Cookson and Eisenack, 1958, pl.11, fig.12
Locus typicus: Omatia, Papua
Stratum typicum: Aptian-Albian
Original description: Cookson and Eisenack, 1958, p.43: Hystrichosphaeridium anthophorum
Shell sphaeroidal and provided with about 10-15 stalked tabular appendages. The stalks of the appendages which are short and sometimes broad, and frequently show the longitudinal fibrils of which they are composed, gradually widen distally, frequently close to the shell, in deep broad terminal expansions with completely and irregularly reticulate walls and continuous smooth or finely serrated outer edges.
Dimensions: Holotype: Shell 70 µm, overall 210 µm; appandages c. 50 µm.
Supplemental description: Davey, 1969, p.147
The shell is subspherical; shell wall smooth to lightly granular. An apical archaeopyle is typically developed and possesses an angular margin. The processes are hollow, buccinate to infundibular, with the distal flared portion perforate. Distally the margins of the processes are usually entire, but may bear one or two small spines. A complete specimen possesses 18 processes, reflecting a tabulation characteristic of this genus. The processes are all of equal size except for the first postcingular (1""") and the posterior intercalary (1p) which are often reduced.
Dimensions: Range of observed specimens: diameter of central body 38(46.3)57 µm, maximum length of processes 18(34.1)43 µm. Number of specimens measured, 8.
Affinities:
Cookson and Eisenack, 1958, p.43-44: Hystrichosphaeridium anthophorum
Hystrichosphaeridium anthophorum is morphologically close to H. pulcherrimum Deflandre and Cookson and H. dictyoplocus Klumpp. It differs from H. pulcherrimum in the more extensive reticulation of the appendages and the entire edge of the terminal expansion, and from H. dictyoplocus in the shorter and somewhat broader appandages and the wider mesh and continuous margin of the terminal expansions.
Brideaux, 1971, p.89: Oligosphaeridium anthophorum is characterized by flaring fenestrate or foveolate processes with entire open margins. The closely related form, O. pulcherrimum (Deflandre and Cookson) Davey and Williams 1966 possesses flaring fenestrate processes but without entire apices. O. dictyophorum (Deflandre and Cookson) Davey and Williams 1969, p.5 appears to differ from these two species in having thin, solid-walled columns and wide-meshed, strongly expanded columns.