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Isabelidinium globosum
Isabelidinium? globosum (Davey, 1970) Lentin and Williams, 1977
Originally Deflandrea, subsequently Isabelia? (combination illegitimate), thirdly (and now) Isabelidinium?. Questionable assignment: Lentin and Williams (1977a, p.167).
Holotype: Davey, 1970, pl.2, fig.3
Locus typicus: Saskatchewan, Canada
Stratum typicum: Cenomanian
Original diagnosis: Davey, 1970, p. 344: Deflandrea globosa
Shell subspherical to subpolygonal, with small number of concentric folds at apex, and very reduced single antapical horn placed asymmetrically. Apical horn, cingulum and sulcus absent. Inner body entirely in contact with outer membrane. Wall smooth to slightly granular. Intercalary archaeopyle, angular, sixsided.
Dimensions: Holotype: shell length 69 µm, shell width 66 µm. Range: shell length 62 (67.5) 78 µm, shell width 48 (58.8) 66 µm. Number of specimens measured, 6.
Original description: Davey, 1970, p. 344: Deflandrea globosa
This species is extremely simple in form, possessing only a very rudimentary antapical horn to mar its smooth outline. The operculum is typically in place and the archaeopyle outline is only discerned with some difficulty.
Affinities:
Davey, 1970, p. 344: Deflandrea globosa
In overall appearance D. globosa strongly resembles D. glomerata. They differ in that D. globosa possesses a very rudimentary antapical horn and that the inner body is entirely in contact with the outer membrane. The lack of an apical horn (apical wrinkles being present), any tabulation and the spherical form indicate that these tw o species are closely related. Because of this and the presence of an intercalary archaeopyle, D. globosa is placed in the genus Defandrea.
Originally Deflandrea, subsequently Isabelia? (combination illegitimate), thirdly (and now) Isabelidinium?. Questionable assignment: Lentin and Williams (1977a, p.167).
Holotype: Davey, 1970, pl.2, fig.3
Locus typicus: Saskatchewan, Canada
Stratum typicum: Cenomanian
Original diagnosis: Davey, 1970, p. 344: Deflandrea globosa
Shell subspherical to subpolygonal, with small number of concentric folds at apex, and very reduced single antapical horn placed asymmetrically. Apical horn, cingulum and sulcus absent. Inner body entirely in contact with outer membrane. Wall smooth to slightly granular. Intercalary archaeopyle, angular, sixsided.
Dimensions: Holotype: shell length 69 µm, shell width 66 µm. Range: shell length 62 (67.5) 78 µm, shell width 48 (58.8) 66 µm. Number of specimens measured, 6.
Original description: Davey, 1970, p. 344: Deflandrea globosa
This species is extremely simple in form, possessing only a very rudimentary antapical horn to mar its smooth outline. The operculum is typically in place and the archaeopyle outline is only discerned with some difficulty.
Affinities:
Davey, 1970, p. 344: Deflandrea globosa
In overall appearance D. globosa strongly resembles D. glomerata. They differ in that D. globosa possesses a very rudimentary antapical horn and that the inner body is entirely in contact with the outer membrane. The lack of an apical horn (apical wrinkles being present), any tabulation and the spherical form indicate that these tw o species are closely related. Because of this and the presence of an intercalary archaeopyle, D. globosa is placed in the genus Defandrea.