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Canningia minor
From Fensome et al., 2019:
Canningia minor Cookson and Hughes, 1964, p.43, pl.8, figs.1–3,5. Holotype: Cookson and Hughes, 1964, pl.8, fig.1. NOW Cyclonephelium minor. Originally Canningia minor, subsequently Canningia? minor, thirdly Batiacasphaera minor, fourthly Chytroeisphaeridia minor, fifthly Kallosphaeridium? minus (combination illegitimate), sixthly Kallosphaeridium? helbyi, seventhly (and now) Cyclonephelium minor. Questionable assignment: Stover and Evitt (1978, p.25). Age: late Albian–early Cenomanian.
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Original description: [Cookson and Hughes, 1964, p.43]:
Diagnosis:
Shell almost circular in outline, in well-preserved examples slightly longer than broad, opening by the removal of an apical segment along a zigzag line, the freed edge of the shell showing notches at intervals; apex with or without a short prominence, antapex usually unindented. Girdle absent; wall c. 1 µm thick, surface scabrate.
Dimensions:
Holotype 70 x 73 µm. Range 42-73 µm long, 36-73 µm broad.
Affinities: (p. 44):
Of the three described species of Canngia C. minor most closely resembles the Australian Aptian species C. colliveri Cookson and Eisenack 1960. However, it can be distinguished from this species by the less frequent occurrence of an apical prominence and indented antapex, its consistently smaller size (average dimensions of 19 specimens 56 x 52 µm), and the finer ornamentation of the shell-membrane.
In the majority of specimens the apex is partially detached and crumpled so that a more accurate ratio of length to breadth has not been possible. Plate 8, fig. 4 shows a specimen with a girdle developed; in spite of several similarities to C. minor we prefer to record this as Canngia? sp.
Canningia minor Cookson and Hughes, 1964, p.43, pl.8, figs.1–3,5. Holotype: Cookson and Hughes, 1964, pl.8, fig.1. NOW Cyclonephelium minor. Originally Canningia minor, subsequently Canningia? minor, thirdly Batiacasphaera minor, fourthly Chytroeisphaeridia minor, fifthly Kallosphaeridium? minus (combination illegitimate), sixthly Kallosphaeridium? helbyi, seventhly (and now) Cyclonephelium minor. Questionable assignment: Stover and Evitt (1978, p.25). Age: late Albian–early Cenomanian.
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Original description: [Cookson and Hughes, 1964, p.43]:
Diagnosis:
Shell almost circular in outline, in well-preserved examples slightly longer than broad, opening by the removal of an apical segment along a zigzag line, the freed edge of the shell showing notches at intervals; apex with or without a short prominence, antapex usually unindented. Girdle absent; wall c. 1 µm thick, surface scabrate.
Dimensions:
Holotype 70 x 73 µm. Range 42-73 µm long, 36-73 µm broad.
Affinities: (p. 44):
Of the three described species of Canngia C. minor most closely resembles the Australian Aptian species C. colliveri Cookson and Eisenack 1960. However, it can be distinguished from this species by the less frequent occurrence of an apical prominence and indented antapex, its consistently smaller size (average dimensions of 19 specimens 56 x 52 µm), and the finer ornamentation of the shell-membrane.
In the majority of specimens the apex is partially detached and crumpled so that a more accurate ratio of length to breadth has not been possible. Plate 8, fig. 4 shows a specimen with a girdle developed; in spite of several similarities to C. minor we prefer to record this as Canngia? sp.