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Impagidinium paradoxum
Impagidinium paradoxum (Wall, 1967) Stover and Evitt, 1978
Originally Leptodinium, subsequently (and now) Impagidinium.
Holotype: Wall, 1967, pl.15, fig.5
Locus typicus: Core A254/330, Yucatan Basin (19¦ 35" N., 84¦ 51" W.)
Stratum typicum: Miocene-Recent
Original diagnosis: Wall, 1967, p. 106: Leptodinium paradoxum
A very small ovoid species with a tabulation 3-4", 0a, 6"", 6g, 5-6""", 1p, 1"""", defined by low sutural septa which are sometimes reduced in the ventral area. Test not exceeding 40 µm.
Dimensions: Test only 29-38 µm; septa around 3 µm. Over 50 specimens.
Original description: Wall, 1967, p. 106: Leptodinium paradoxum
The test is ovoid to polyhedral and divided equatorially into epithecal and hypothecal regions by a relatively wide, descending girdle displaced by its own width ventrally. The longitudinal furrow broadens on to the hypotheca and is weakly inclined. The sutural septa are hyaline and very low (equivalent to approximately one-tenth of a diameter); the test varies from smooth to microgranular. The apical plate series comprises two pentagonal dorsal areas and a linear, median compound ventral area which may be divided longitudinally to form two areas (1" and 4"). Precingular areas 1"" to 5"" are subrectangular, 3"" being an archeopyle; 6"" is triangular and either incompletely separated from the furrow or possessing a concave outer margin. The furrow may be divided into three platelet-areas by very reduced septa. The girdle plate-areas are rectangular; sections of the septa outlining 5g and 6g may be missing. There are usually five postcingular areas but in some specimens there are six due to the additional presence of a small linear first post-cingular area, 1""". There is a small posterior intercalary area and a quadrangular antapical area.
Affinities:
Wall, 1967, p. 106: Leptodinium paradoxum
L. paradoxum recalls L. patulum in some details of its tabulation but is smaller. It differs from L. aculeatum in outline and in configuration of the sixth precingular area.
Originally Leptodinium, subsequently (and now) Impagidinium.
Holotype: Wall, 1967, pl.15, fig.5
Locus typicus: Core A254/330, Yucatan Basin (19¦ 35" N., 84¦ 51" W.)
Stratum typicum: Miocene-Recent
Original diagnosis: Wall, 1967, p. 106: Leptodinium paradoxum
A very small ovoid species with a tabulation 3-4", 0a, 6"", 6g, 5-6""", 1p, 1"""", defined by low sutural septa which are sometimes reduced in the ventral area. Test not exceeding 40 µm.
Dimensions: Test only 29-38 µm; septa around 3 µm. Over 50 specimens.
Original description: Wall, 1967, p. 106: Leptodinium paradoxum
The test is ovoid to polyhedral and divided equatorially into epithecal and hypothecal regions by a relatively wide, descending girdle displaced by its own width ventrally. The longitudinal furrow broadens on to the hypotheca and is weakly inclined. The sutural septa are hyaline and very low (equivalent to approximately one-tenth of a diameter); the test varies from smooth to microgranular. The apical plate series comprises two pentagonal dorsal areas and a linear, median compound ventral area which may be divided longitudinally to form two areas (1" and 4"). Precingular areas 1"" to 5"" are subrectangular, 3"" being an archeopyle; 6"" is triangular and either incompletely separated from the furrow or possessing a concave outer margin. The furrow may be divided into three platelet-areas by very reduced septa. The girdle plate-areas are rectangular; sections of the septa outlining 5g and 6g may be missing. There are usually five postcingular areas but in some specimens there are six due to the additional presence of a small linear first post-cingular area, 1""". There is a small posterior intercalary area and a quadrangular antapical area.
Affinities:
Wall, 1967, p. 106: Leptodinium paradoxum
L. paradoxum recalls L. patulum in some details of its tabulation but is smaller. It differs from L. aculeatum in outline and in configuration of the sixth precingular area.