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Batiacasphaera spumosa
Batiacasphaera spumosa, (Brideaux, 1977), Below, 1981
Originally Canningia, subsequently Batiacasphaera?, thirdly (and now) Batiacasphaera. At the time of the transfer, Below, 1981, questionably included this species in Batiacasphaera. However, Helby, 1987, considered the combination to be without question. Kumar, 1986, also transferred this species to Batiacasphaera without question.
Holotype: Brideaux, 1977, pl.3, figs 9,14
Locus typicus: Richardson Mountains, Mackenzie district, Canada
Stratum typicum: Albian
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Original description as Canningia spumosa: [Brideaux, 1977, p. 12]:
Description:
Shape: Pericyst ambitus ovoid to rounded; pericyst profile ovoid the apex produced into a short rounded apical horn, 3-4 µm long, the antapex rounded and without developed prominences. Endocyst as above, the two layers closely appressed. Pericoel not developed; slight dorso-ventral compression.
Phragma: Periphragm from 1.0-1.5 µm thick in optical section, fibrous structure formed of thin rod-shaped pore canals and intervening solid periphragm, the pores opening as puncta on the surface; periphragm surface sculptured with discrete grana, cones, bacula or spines from 1-3 µm high and about 1 µm wide, sculpture set occasionally on low vermiculate or vermiculoreticulate ridges less than 0.5 µm high and wide.
Endophragm thin, less than 0.5 µm thick and smooth.
Paratabulation: Paratabulation of 4", 6", 9c, ?p, denoted by shape of the archeopyle and the isolated opercula, and by development of accessory parasutures in the precingular paraplate series; other evidence for paratabulation lacking.
Endophragm showing no evidence of paratabulation.
Archeopyle/operculum: Archeopyle formed by the loss of four apical paraplates. Operculum simple, attached on the holotype specimen at the boundary of the parasulcal region and the posterior margin of the paraplate 1", otherwise apparently free; the two layers closely appressed and separating as one unit. Formula Aa? or A.
Pericingulum/perisulcus: No expression of pericingulum; perisulcal position indicated only by position of the perisulcal notch.
Dimensions:
Pericyst length, 63 µm; pericyst width, 40-70 µm.
Affinities:
Canningia spumosa superficially resembles Canningia circularis Cookson and Eisenack 1971, but differs in being smalier and in having a fibrous periphragm with variable sculpture of grana, coni, bacula, or spines.
Originally Canningia, subsequently Batiacasphaera?, thirdly (and now) Batiacasphaera. At the time of the transfer, Below, 1981, questionably included this species in Batiacasphaera. However, Helby, 1987, considered the combination to be without question. Kumar, 1986, also transferred this species to Batiacasphaera without question.
Holotype: Brideaux, 1977, pl.3, figs 9,14
Locus typicus: Richardson Mountains, Mackenzie district, Canada
Stratum typicum: Albian
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Original description as Canningia spumosa: [Brideaux, 1977, p. 12]:
Description:
Shape: Pericyst ambitus ovoid to rounded; pericyst profile ovoid the apex produced into a short rounded apical horn, 3-4 µm long, the antapex rounded and without developed prominences. Endocyst as above, the two layers closely appressed. Pericoel not developed; slight dorso-ventral compression.
Phragma: Periphragm from 1.0-1.5 µm thick in optical section, fibrous structure formed of thin rod-shaped pore canals and intervening solid periphragm, the pores opening as puncta on the surface; periphragm surface sculptured with discrete grana, cones, bacula or spines from 1-3 µm high and about 1 µm wide, sculpture set occasionally on low vermiculate or vermiculoreticulate ridges less than 0.5 µm high and wide.
Endophragm thin, less than 0.5 µm thick and smooth.
Paratabulation: Paratabulation of 4", 6", 9c, ?p, denoted by shape of the archeopyle and the isolated opercula, and by development of accessory parasutures in the precingular paraplate series; other evidence for paratabulation lacking.
Endophragm showing no evidence of paratabulation.
Archeopyle/operculum: Archeopyle formed by the loss of four apical paraplates. Operculum simple, attached on the holotype specimen at the boundary of the parasulcal region and the posterior margin of the paraplate 1", otherwise apparently free; the two layers closely appressed and separating as one unit. Formula Aa? or A.
Pericingulum/perisulcus: No expression of pericingulum; perisulcal position indicated only by position of the perisulcal notch.
Dimensions:
Pericyst length, 63 µm; pericyst width, 40-70 µm.
Affinities:
Canningia spumosa superficially resembles Canningia circularis Cookson and Eisenack 1971, but differs in being smalier and in having a fibrous periphragm with variable sculpture of grana, coni, bacula, or spines.