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Ataxiodinium choane
Ataxiodinium choane, Reid, 1974
Originally (and now) Ataxiodinium, subsequently Planinosphaeridium. Edwards and Andrle (1992, p.265) retained this species in Ataxiodinium. Taxonomic senior synonym: Planinosphaeridium membranaceum, according to Dale (1976, p.45; footnote to table II) - however, Wall et al. (1977, p.149) retained Ataxiodinium (as Planinosphaeridium) choane.
Holotype: Reid, 1974, pl.1, figs.1-2; and Fensome et al., 1993a, figs.1-2 - p.1053.
Locus typicus: Severn Estuary, England
Stratum typicum: Recent
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Original description: [Reid 1974. p. 588-589]:
Diagnosis:
Inner capsule circular to subcircular and single walled, covered by an outer expanded crenulate membrane attached around the archeopyle and by funnel-shaped depressions to the inner wall.
Description:
The inner capsule is usually circular in outline, but may be slightly elongated in a polar direction. The outer microgranular membrane at times appears to form fields and a depression indicating the ventral sulcus. The wall of the inner capsule is thin 0.6 µm, single layered, yellow in colour and appears to have a smooth surface.
A precingular archeopyle is thought to be present because of its similar shape to the archeopyles of other known precingular genera.
Dimensions:
Holotype: inner capsule 30x30 µm, complete test 49x49 µm; Range: inner capsule 28x26 to 40x37 µm, complete test 47x47 to 50x58 µm.
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Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Ataxiodinium choane Reid, 1974, has a crenulate membrane attached around the archeopyle and by funnel shaped depressions in the endocyst. Size: overall 47 x 47 to 50 x 58 µm, capsule 28 x 26 to 40 x 37 µm.
Originally (and now) Ataxiodinium, subsequently Planinosphaeridium. Edwards and Andrle (1992, p.265) retained this species in Ataxiodinium. Taxonomic senior synonym: Planinosphaeridium membranaceum, according to Dale (1976, p.45; footnote to table II) - however, Wall et al. (1977, p.149) retained Ataxiodinium (as Planinosphaeridium) choane.
Holotype: Reid, 1974, pl.1, figs.1-2; and Fensome et al., 1993a, figs.1-2 - p.1053.
Locus typicus: Severn Estuary, England
Stratum typicum: Recent
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Reid 1974. p. 588-589]:
Diagnosis:
Inner capsule circular to subcircular and single walled, covered by an outer expanded crenulate membrane attached around the archeopyle and by funnel-shaped depressions to the inner wall.
Description:
The inner capsule is usually circular in outline, but may be slightly elongated in a polar direction. The outer microgranular membrane at times appears to form fields and a depression indicating the ventral sulcus. The wall of the inner capsule is thin 0.6 µm, single layered, yellow in colour and appears to have a smooth surface.
A precingular archeopyle is thought to be present because of its similar shape to the archeopyles of other known precingular genera.
Dimensions:
Holotype: inner capsule 30x30 µm, complete test 49x49 µm; Range: inner capsule 28x26 to 40x37 µm, complete test 47x47 to 50x58 µm.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Ataxiodinium choane Reid, 1974, has a crenulate membrane attached around the archeopyle and by funnel shaped depressions in the endocyst. Size: overall 47 x 47 to 50 x 58 µm, capsule 28 x 26 to 40 x 37 µm.