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Hystrichosphaeridium assamicum
From Fensome et al., 2019:
Hystrichosphaeridium assamicum Sah et al., 1970, p.146–147, pl.2, figs.20–21. Holotype: Sah et al., 1970, pl.2, fig.20. Originally Hystrichosphaeridium, subsequently (and now) Hystrichosphaeridium?. Questionable assignment: Stover and Evitt(1978, p.56) as a problematic species. Jain (1982, p.52) recommended that this name be restricted to the holotype. Age: Late Cretaceous.
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Original description: [Sah et al., 1970]:
Hystrichosphaeridium assamicum sp. nov.
PI. 2, Figs. 20-21
Holotype- PI. 2, Fig. 20. Size 76 X 74 μ.
Slide no. 3648.
No. of specimens studied- 15.
Diagnosis- Cysts subcircular-oval, 70-84 X 66-80 μ; archeopyle apical; tubular processes less than thirty, mostly with tufted tips; cell membrane laevigate.
Description- Cysts mostly subcircular with generally closed archeopyle. When open, the sulcal notch appears less prominent. Processes ± bacular, up to 30 μ in length; ramifications not well developed. Cyst membrane up to 1·5 μ thick, laevigate.
Comparison - The present species resembles Hystrichosphaeridium difficile Manum (1964) in shape, size range, number of processes and in the nature of the archeopyle but the latter differs in having a distinctly sculptured cyst membrane and comparatively more ramified processes. H. stellatum Maier (1959) has densely placed bacular processes which are unequal in length. H. zoicum is smaller in size and has comparatively shorter bacular processes.
Hystrichosphaeridium assamicum Sah et al., 1970, p.146–147, pl.2, figs.20–21. Holotype: Sah et al., 1970, pl.2, fig.20. Originally Hystrichosphaeridium, subsequently (and now) Hystrichosphaeridium?. Questionable assignment: Stover and Evitt(1978, p.56) as a problematic species. Jain (1982, p.52) recommended that this name be restricted to the holotype. Age: Late Cretaceous.
---------------------------------------------------------------------------------------------------
Original description: [Sah et al., 1970]:
Hystrichosphaeridium assamicum sp. nov.
PI. 2, Figs. 20-21
Holotype- PI. 2, Fig. 20. Size 76 X 74 μ.
Slide no. 3648.
No. of specimens studied- 15.
Diagnosis- Cysts subcircular-oval, 70-84 X 66-80 μ; archeopyle apical; tubular processes less than thirty, mostly with tufted tips; cell membrane laevigate.
Description- Cysts mostly subcircular with generally closed archeopyle. When open, the sulcal notch appears less prominent. Processes ± bacular, up to 30 μ in length; ramifications not well developed. Cyst membrane up to 1·5 μ thick, laevigate.
Comparison - The present species resembles Hystrichosphaeridium difficile Manum (1964) in shape, size range, number of processes and in the nature of the archeopyle but the latter differs in having a distinctly sculptured cyst membrane and comparatively more ramified processes. H. stellatum Maier (1959) has densely placed bacular processes which are unequal in length. H. zoicum is smaller in size and has comparatively shorter bacular processes.