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Circulodinium asperum
Circulodinium asperum, (Singh, 1971), Helby, 1987
Originally Canningia, subsequently Canningia?, thirdly Epelidosphaeridia, fourthly Cyclonephelium, fifthly (and now) Circulodinium.
Holotype: Singh, 1971, pl.50, fig.1
Locus typicus: Peace River Area, Canada
Stratum typicum: Middle Albian
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Original description as Canningia aspera: [Singh, 1971, p.322]:
Description:
Test roughly five sided and widest at the equator; length and breadth of the body almost equal; body with one apical and two antapical, barely discernible prominences indicated by slight projections in the outline and thicker ornamentation;
cingulum faint, bordered on either side by a row of closely spaced, fine spinules;
archaeopyle apical and opening along a downwardly directed curved line;
body ornamented by thick, irregular shaped elevations surmounted by 2-4 µm long, conical spines; body wall about 2.5 µm thick.
Dimensions:
Size range: Length of test 96(100)105 µm. Breadth of test 94(97)103 µm.
Affinities:
Canningia aspera differs from C. rotundata, which has a vermiculate surface ornamentation and a slight, median, antapical prominence, and lacks the cingulum.
Originally Canningia, subsequently Canningia?, thirdly Epelidosphaeridia, fourthly Cyclonephelium, fifthly (and now) Circulodinium.
Holotype: Singh, 1971, pl.50, fig.1
Locus typicus: Peace River Area, Canada
Stratum typicum: Middle Albian
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description as Canningia aspera: [Singh, 1971, p.322]:
Description:
Test roughly five sided and widest at the equator; length and breadth of the body almost equal; body with one apical and two antapical, barely discernible prominences indicated by slight projections in the outline and thicker ornamentation;
cingulum faint, bordered on either side by a row of closely spaced, fine spinules;
archaeopyle apical and opening along a downwardly directed curved line;
body ornamented by thick, irregular shaped elevations surmounted by 2-4 µm long, conical spines; body wall about 2.5 µm thick.
Dimensions:
Size range: Length of test 96(100)105 µm. Breadth of test 94(97)103 µm.
Affinities:
Canningia aspera differs from C. rotundata, which has a vermiculate surface ornamentation and a slight, median, antapical prominence, and lacks the cingulum.