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Impagidinium sphaericum
Impagidinium sphaericum (Wall, 1967) Lentin and Williams, 1981
Originally Leptodinium, subsequently (and now) Impagidinium.
Holotype: Wall, 1967, pl.15, fig.11-12
Locus typicus: Caribbean Sea, Yucatan Basin
Stratum typicum: Pleistocene-Holocene
Original diagnosis: Wall, 1967, p.108: Leptodinium sphaericum
A spherical to polyhedral species with very low sutural septa defining a tabulation 4", 0a, 6"", 6g, 6""", 1p, 1""""; test with a small apical boss.
Size approximately 40-58 µm.
Description: Wall, 1967, p.108: Leptodinium sphaericum
The test is spherical to polyhedral and has a small blunt apical boss. Its surface is weakly microgranular and ornamented by very low sutural septa, only a few microns high. Its tabulation is 4, 0a, 6"", 6g, 6""", 1p, 1"""". The girdle is narrow, descending, composed of rectangular plate-areas and divides the test equatorially into equal epithecal and hypothecal regions; ventrally the girdle is displaced by slightly more than its own width. The longitudinal furrow is quite strongly inclined and comprises five platelet-areas, namely, anterior, right accessory, right and left sulcal, and posterior sulcal; of these, the right sulcal is very small while the posterior sulcal is large. There are two pentagonal dorsal apical areas and two linear median anterior ventral areas in the apical series. The precingular series comprises six areas, of which the third forms an archeopyle and the sixth is triangular with a concave left margin. There are six postcingular areas, 1""" being a small linear structure on the left margin of the sulcus; the other areas are subrectangular. The posterior intercalary area is relatively large and anterior to a quadrangular antapical area (1"""").
Originally Leptodinium, subsequently (and now) Impagidinium.
Holotype: Wall, 1967, pl.15, fig.11-12
Locus typicus: Caribbean Sea, Yucatan Basin
Stratum typicum: Pleistocene-Holocene
Original diagnosis: Wall, 1967, p.108: Leptodinium sphaericum
A spherical to polyhedral species with very low sutural septa defining a tabulation 4", 0a, 6"", 6g, 6""", 1p, 1""""; test with a small apical boss.
Size approximately 40-58 µm.
Description: Wall, 1967, p.108: Leptodinium sphaericum
The test is spherical to polyhedral and has a small blunt apical boss. Its surface is weakly microgranular and ornamented by very low sutural septa, only a few microns high. Its tabulation is 4, 0a, 6"", 6g, 6""", 1p, 1"""". The girdle is narrow, descending, composed of rectangular plate-areas and divides the test equatorially into equal epithecal and hypothecal regions; ventrally the girdle is displaced by slightly more than its own width. The longitudinal furrow is quite strongly inclined and comprises five platelet-areas, namely, anterior, right accessory, right and left sulcal, and posterior sulcal; of these, the right sulcal is very small while the posterior sulcal is large. There are two pentagonal dorsal apical areas and two linear median anterior ventral areas in the apical series. The precingular series comprises six areas, of which the third forms an archeopyle and the sixth is triangular with a concave left margin. There are six postcingular areas, 1""" being a small linear structure on the left margin of the sulcus; the other areas are subrectangular. The posterior intercalary area is relatively large and anterior to a quadrangular antapical area (1"""").