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Stiphrosphaeridium dictyophorum
Stiphrosphaeridium dictyophorum (Cookson and Eisenack, 1958) Lentin and Williams, 1985
Originally Hystrichosphaeridium, subsequently Baltisphaeridium (an acritarch genus), thirdly Oligosphaeridium, fourthly (and now) Stiphrosphaeridium. Davey,
1982 did not validly publish the combination Stiphrosphaeridium dictyophorum, since he did not give a reference for Cookson and Eisenack, 1958.
Holotype: Cookson and Eisenack, 1958, pl.11, fig.14; Fensome et al., 1993a, fig.1 — p.1125.
Locus typicus: Omati, Papua, New Guinea
Stratum typicum: Late Jurassic
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999
Stiphrosphaeridium dictyophorum (Cookson and Eisenack, 1958) Lentin and Williams, 1985. Diagnosis from Cookson and Eisenack (1958, p.44). Shell spheroidal, provided with 10-15 processes which have rather short, apparently solid stems, and abruptly delimited, widely expanded and open meshed terminal expansions with a smooth, continuous edge. Size: holotype, overall diameter 140 µm, central body diameter 71 µm, length of processes 42-47 µm.
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Original description: Coocson and Eisenack, 1958, p. 44: Hystrichosphaeridium dictyophorum
Shell sphaeroidal, provided with 10-15 appendages which have rather short, appearantly solid stems, and abruply delimited, widely expanded and open meshed terminal expansions with smooth, continuous edge.
Dimensions: Holotype: diameter of shell 71 µm, overall diameter 140 µm; appendages 42-47 µm.
Supplemental description: Davey, 1982, p. 17:
S. dictyophorum illustrates all the characteristics of the genus. Most of the major processes are solid proximately for up to half of their length and only in the largest processes, mainly the dorsal postcingular and the antapical, do the fenestrations extend to the body surface. Thus, in the latter cases, it could be interpreted that the two to four processes arising from the surface constitute narrow or restricted annulate process complexes. Parasutural processes, additional to the posterior parasulcal, are rare as is the first postcingular process (1'''). The traberculae are smooth to slightly denticulate distally. An apical archaeopyle is usually developed.
Originally Hystrichosphaeridium, subsequently Baltisphaeridium (an acritarch genus), thirdly Oligosphaeridium, fourthly (and now) Stiphrosphaeridium. Davey,
1982 did not validly publish the combination Stiphrosphaeridium dictyophorum, since he did not give a reference for Cookson and Eisenack, 1958.
Holotype: Cookson and Eisenack, 1958, pl.11, fig.14; Fensome et al., 1993a, fig.1 — p.1125.
Locus typicus: Omati, Papua, New Guinea
Stratum typicum: Late Jurassic
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999
Stiphrosphaeridium dictyophorum (Cookson and Eisenack, 1958) Lentin and Williams, 1985. Diagnosis from Cookson and Eisenack (1958, p.44). Shell spheroidal, provided with 10-15 processes which have rather short, apparently solid stems, and abruptly delimited, widely expanded and open meshed terminal expansions with a smooth, continuous edge. Size: holotype, overall diameter 140 µm, central body diameter 71 µm, length of processes 42-47 µm.
--------------------------------------------------
Original description: Coocson and Eisenack, 1958, p. 44: Hystrichosphaeridium dictyophorum
Shell sphaeroidal, provided with 10-15 appendages which have rather short, appearantly solid stems, and abruply delimited, widely expanded and open meshed terminal expansions with smooth, continuous edge.
Dimensions: Holotype: diameter of shell 71 µm, overall diameter 140 µm; appendages 42-47 µm.
Supplemental description: Davey, 1982, p. 17:
S. dictyophorum illustrates all the characteristics of the genus. Most of the major processes are solid proximately for up to half of their length and only in the largest processes, mainly the dorsal postcingular and the antapical, do the fenestrations extend to the body surface. Thus, in the latter cases, it could be interpreted that the two to four processes arising from the surface constitute narrow or restricted annulate process complexes. Parasutural processes, additional to the posterior parasulcal, are rare as is the first postcingular process (1'''). The traberculae are smooth to slightly denticulate distally. An apical archaeopyle is usually developed.