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Hafniasphaera septata
From Fensome et al., 2019:
Hafniasphaera septata (Cookson and Eisenack, 1967b, p.253–254, pl.42, figs.6–10; text-fig.1) Hansen, 1977, p.16. Emendation: McLean, 1971, p.730, as Spiniferites septatus. Holotype: Cookson and Eisenack, 1967b, pl.42, fig.6; Eisenack and Kjellström, 1975b, uppermost figure — p.984w; Fensome et al., 1996, fig.1 — p.2356. Originally Baltisphaeridium (Appendix A), subsequently Spiniferites, thirdly (and now) Hafniasphaera, fourthly Achomosphaera, fifthly Rivernookia. Williams et al. (1998, p.261) retained this species in Hafniasphaera. Age: Late Paleocene.
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Locus typicus: Rivernook Member of Dilwyn Clay, Victoria, Australia
Stratum typicum: Late Paleocene
Original diagnosis: Cookson and Eisenack, 1967, p.253: Baltisphaeridium septatum
Shell spherical, thin-walled with a closely and rather coarsely apparently granular surface and a variable number of radially arranged appendages which approximate in length to the radius of the shell. A "marginal zone" often present, given the impression that the shell is thick-walled, is, in fact, due to compression.
Original description: Cookson and Eisenack, 1967, p.253: Baltisphaeridium septatum
The appendages vary in size, shape and structure. The majority narrow somewhat from a broadened base and divide distally into two or three straight or curved tapering branches with closed, pointed or minutely bifurcate tips. The larger appendages are typically hollow and septate throughout; in the finer to thread-like ones, on the contrary the degree of septation is often difficult to determine and their distal portions, at least, appear to be solid. A few of the appendages are unbranched. A pylome has been seen in a few specimens.
Dimensions: Holotype: overall diameter c. 80 µm diameter of shell c. 57 µm, appendages 10-18 µm long. Range: shell diameter c. 42-58 µm.
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Hafniasphaera septata (Cookson and Eisenack, 1967b) Hansen, 1977, emend. McLean, 1971. Diagnosis modified from Cookson and Eisenack (1967b), shell spherical, thin-walled with a closely and rather coarsely, apparently granular surface and a variable number of radially arranged processes, whose length is approximately equal to the radius of the shell. A “marginal zone” often present, giving the impression that the shell is thick-walled, is in fact due to compression. The processes vary in size, shape and structure. The majority narrow somewhat from a broadened base and divide distally into two or three straight or curved tapering branches with closed, pointed or minutely bifurcate tips. The larger processes are typically hollow and septate throughout; however, in the finer to thread-like ones, the degree of septation is often difficult to determine and their distal portions at least appear to be solid. A few of the processes are unbranched.An archeopyle has been seen in a few specimens Emended description, from McLean (1972). Cyst main body spheroidal to ovoidal with gonally and intergonally distributed processes; process positions in conjunction with rarely developed, weakly defined sutural ridges indicate tabulation of 3', 0a, 6", 6c, 5?”’, 1p, 1"”. Archeopyle precingular (Type P) with simple, free operculum; corresponds to plate 3". Cingulum reflected by processes; laevorotatory; ends displaced vertically about one cingulum width. Hypotract ventral tabulation weakly developed, obscuring sulcal outline. Cyst wall appears bilayered in optical section, with compact inner layer about 1 µm thick and an outer layer 1.5-3 µm thick (constant for a specimen) constructed of closely appressed, bubble-like elements up to 2.5 µm in diameter. Processes parallel sided to slightly tapering, with bluntly rounded closed tips; two to three relatively small, essentially parallel sided, blunt tipped branches (that may also be branched) extend from most process tips. Process bases constructed of bubble-like elements; process trunks and branches hollow but compartmented by transverse septa. Size: holotype, overall diameter ca. 80 µm, diameter of shell ca. 57 µm, processes 10-18 µm, range overall diameter 42-58 µm.
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Hafniasphaera septata (Cookson and Eisenack, 1967b, p.253–254, pl.42, figs.6–10; text-fig.1) Hansen, 1977, p.16. Emendation: McLean, 1971, p.730, as Spiniferites septatus. Holotype: Cookson and Eisenack, 1967b, pl.42, fig.6; Eisenack and Kjellström, 1975b, uppermost figure — p.984w; Fensome et al., 1996, fig.1 — p.2356. Originally Baltisphaeridium (Appendix A), subsequently Spiniferites, thirdly (and now) Hafniasphaera, fourthly Achomosphaera, fifthly Rivernookia. Williams et al. (1998, p.261) retained this species in Hafniasphaera. Age: Late Paleocene.
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Locus typicus: Rivernook Member of Dilwyn Clay, Victoria, Australia
Stratum typicum: Late Paleocene
Original diagnosis: Cookson and Eisenack, 1967, p.253: Baltisphaeridium septatum
Shell spherical, thin-walled with a closely and rather coarsely apparently granular surface and a variable number of radially arranged appendages which approximate in length to the radius of the shell. A "marginal zone" often present, given the impression that the shell is thick-walled, is, in fact, due to compression.
Original description: Cookson and Eisenack, 1967, p.253: Baltisphaeridium septatum
The appendages vary in size, shape and structure. The majority narrow somewhat from a broadened base and divide distally into two or three straight or curved tapering branches with closed, pointed or minutely bifurcate tips. The larger appendages are typically hollow and septate throughout; in the finer to thread-like ones, on the contrary the degree of septation is often difficult to determine and their distal portions, at least, appear to be solid. A few of the appendages are unbranched. A pylome has been seen in a few specimens.
Dimensions: Holotype: overall diameter c. 80 µm diameter of shell c. 57 µm, appendages 10-18 µm long. Range: shell diameter c. 42-58 µm.
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Hafniasphaera septata (Cookson and Eisenack, 1967b) Hansen, 1977, emend. McLean, 1971. Diagnosis modified from Cookson and Eisenack (1967b), shell spherical, thin-walled with a closely and rather coarsely, apparently granular surface and a variable number of radially arranged processes, whose length is approximately equal to the radius of the shell. A “marginal zone” often present, giving the impression that the shell is thick-walled, is in fact due to compression. The processes vary in size, shape and structure. The majority narrow somewhat from a broadened base and divide distally into two or three straight or curved tapering branches with closed, pointed or minutely bifurcate tips. The larger processes are typically hollow and septate throughout; however, in the finer to thread-like ones, the degree of septation is often difficult to determine and their distal portions at least appear to be solid. A few of the processes are unbranched.An archeopyle has been seen in a few specimens Emended description, from McLean (1972). Cyst main body spheroidal to ovoidal with gonally and intergonally distributed processes; process positions in conjunction with rarely developed, weakly defined sutural ridges indicate tabulation of 3', 0a, 6", 6c, 5?”’, 1p, 1"”. Archeopyle precingular (Type P) with simple, free operculum; corresponds to plate 3". Cingulum reflected by processes; laevorotatory; ends displaced vertically about one cingulum width. Hypotract ventral tabulation weakly developed, obscuring sulcal outline. Cyst wall appears bilayered in optical section, with compact inner layer about 1 µm thick and an outer layer 1.5-3 µm thick (constant for a specimen) constructed of closely appressed, bubble-like elements up to 2.5 µm in diameter. Processes parallel sided to slightly tapering, with bluntly rounded closed tips; two to three relatively small, essentially parallel sided, blunt tipped branches (that may also be branched) extend from most process tips. Process bases constructed of bubble-like elements; process trunks and branches hollow but compartmented by transverse septa. Size: holotype, overall diameter ca. 80 µm, diameter of shell ca. 57 µm, processes 10-18 µm, range overall diameter 42-58 µm.
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