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Canningia ringnesiorum
Canningia? ringnesiorum, Manum and Cookson, 1964
Now Kallosphaeridium?. Originally Canningia, subsequently Canningia?, thirdly Batiacasphaera, fourthly Chytroeisphaeridia, fifthly (and now) Kallosphaeridium?. Stover and Evitt, 1978, considered this to be a provisionally accepted species of Canningia.
Holotype: Manum and Cookson, 1964, pl.2, fig.10
Locus typicus: Ellef Ringnes Island, Arctic Canada
Stratum typicum: Campanian-Maastrichtian
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Original description: [Manum and Cookson, 1964, p.15-160]:
Description:
Shell almost circular, sometimes slightly broader than long, with or without a slight apical projection.
Archeopyle apical, formed by the rupture of the shell along a more or less straight line a short distance behind the apex, sometimes small V-shaped notches can be observed along the edge.
Wall thin, in surface view with a finely dotted pattern, in optical section the ornament is seen to be composed of somewhat club-shaped elements c. 1.0 µm Iong.
Dimensions:
Holotype: 92 µm long, 93 µm broad.
Range: 64-102 µm long, 57-100 µm broad.
Affinities:
Of the described species of Canningia, C. ringnesii comes closest to C. colliveri Cookson & Eisenack (1960). It differs from the latter in the absence of an antapical indentation and in the composition of the shell-wall.
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Supplemental description:
Hultberg, 1985, p. 111:
Description:
Cornucavate cyst, composed of endophragm and periphragm, separated by minute pericoels in the very small apical and antapical protrusions. The surface of the endophragm is granulate. The surface of the periphragm is smooth. The shape of the cyst is subspherical with a very small apical protrusion, and two very small antapical protrusions.
No indication of paratabulation is present, except the archeopyle, which enables the recognition of paraplates 1"" to 6"". Accessory archeopyle sutures in the operculum enable the recognition of paraplates 1" to 4". No ornamentation is present. The archeopyle is apical, type tA. Operculum free.
Paracingulum is indicated by very faint lineations on the dorsal surface of the periphragm. Paracingulum is almost circular. Parasulcus is not indicated.
Dimensions:
Size - 60-64 µm (length), 61-66 µm (breadth).
Now Kallosphaeridium?. Originally Canningia, subsequently Canningia?, thirdly Batiacasphaera, fourthly Chytroeisphaeridia, fifthly (and now) Kallosphaeridium?. Stover and Evitt, 1978, considered this to be a provisionally accepted species of Canningia.
Holotype: Manum and Cookson, 1964, pl.2, fig.10
Locus typicus: Ellef Ringnes Island, Arctic Canada
Stratum typicum: Campanian-Maastrichtian
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Original description: [Manum and Cookson, 1964, p.15-160]:
Description:
Shell almost circular, sometimes slightly broader than long, with or without a slight apical projection.
Archeopyle apical, formed by the rupture of the shell along a more or less straight line a short distance behind the apex, sometimes small V-shaped notches can be observed along the edge.
Wall thin, in surface view with a finely dotted pattern, in optical section the ornament is seen to be composed of somewhat club-shaped elements c. 1.0 µm Iong.
Dimensions:
Holotype: 92 µm long, 93 µm broad.
Range: 64-102 µm long, 57-100 µm broad.
Affinities:
Of the described species of Canningia, C. ringnesii comes closest to C. colliveri Cookson & Eisenack (1960). It differs from the latter in the absence of an antapical indentation and in the composition of the shell-wall.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Supplemental description:
Hultberg, 1985, p. 111:
Description:
Cornucavate cyst, composed of endophragm and periphragm, separated by minute pericoels in the very small apical and antapical protrusions. The surface of the endophragm is granulate. The surface of the periphragm is smooth. The shape of the cyst is subspherical with a very small apical protrusion, and two very small antapical protrusions.
No indication of paratabulation is present, except the archeopyle, which enables the recognition of paraplates 1"" to 6"". Accessory archeopyle sutures in the operculum enable the recognition of paraplates 1" to 4". No ornamentation is present. The archeopyle is apical, type tA. Operculum free.
Paracingulum is indicated by very faint lineations on the dorsal surface of the periphragm. Paracingulum is almost circular. Parasulcus is not indicated.
Dimensions:
Size - 60-64 µm (length), 61-66 µm (breadth).