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Impagidinium hannahii
Impagidinium hannahii Willumsen, 2011, p.222,224, figs.9B–C; figs.10A–B,E.
Holotype: Willumsen, 2011, fig.9B.
Age: late Maastrichtian–early Paleocene.
Original description (Willumsen, 2011):
Impagidinium hannahii sp. nov. (Figs 9B, C; 10A, B, E)
Types. Holotype, Mead Stream, P30/f906, slide L18315/3, 6 mm, EF: T49,3 (Fig. 9B). Paratype, Mead Stream, P30/f334, slide L18319/3, 6 mm, EF: K46 (Fig. 9C).
Type unit and locality. Mead Hill Formation, Mead Stream section, Clarence Valley, Marlborough, New Zealand.
Etymology. After palynologist Dr Michael Hannah, the principal superviser of the author’s PhD /project.
Diagnosis. A medium-sized Impagidinium species with hyaline, parasutural septa that are lacerate at the margin. Sutural ridges are most developed in the gonal positions.
Description. A circular medium-sized proximate cyst with sutural ridges that are 10– 14 µm high and best developed in the gonal positions. The crests between the gonal areas are finely foveolate to scrabate and have a characteristic lacerate edge (Figs 10A, B). The cingulum is 6 µm wide. Paraplates 6c and 1c are displaced about 6 µm in the midventral area. Tabulation is indicated by septa except in the midventral area. Septa have not been observed in the sulcal field. Precingular archaeopyle formed by the loss of plate 3’’. Most specimens have a free operculum. Total diameter 49(60)69 µm [8 specimens measured]. Cingulum 5(6)7 wide [4 specimens measured]. Septa 10(12)14 µm high [8 specimens measured].
Remarks. Impagidinium hannahii sp. nov. differs from I. celineae Jan du Cheˆne, 1988 and I. patulum Wall, 1967 and I. antecarcerum, de Verteuil & Norris 1996 by having septa that are lacerate at the margin, gonally expanded and fovealate.
Age and distribution. Impagidinium hannahii FO is below the sampled section, but it occurs consistently up to the upper part of the early Paleocene radiolarian zone RP2 and is sporadic within radiolarian zone RP3 corresponding to an interval from ca 64.7–64.3 Ma. This species is common in uppermost Maastrichtian strata. It was identified from Branch Stream, Grey River, Mead Stream, mid-Waipara River and Tawanui Stream.
Holotype: Willumsen, 2011, fig.9B.
Age: late Maastrichtian–early Paleocene.
Original description (Willumsen, 2011):
Impagidinium hannahii sp. nov. (Figs 9B, C; 10A, B, E)
Types. Holotype, Mead Stream, P30/f906, slide L18315/3, 6 mm, EF: T49,3 (Fig. 9B). Paratype, Mead Stream, P30/f334, slide L18319/3, 6 mm, EF: K46 (Fig. 9C).
Type unit and locality. Mead Hill Formation, Mead Stream section, Clarence Valley, Marlborough, New Zealand.
Etymology. After palynologist Dr Michael Hannah, the principal superviser of the author’s PhD /project.
Diagnosis. A medium-sized Impagidinium species with hyaline, parasutural septa that are lacerate at the margin. Sutural ridges are most developed in the gonal positions.
Description. A circular medium-sized proximate cyst with sutural ridges that are 10– 14 µm high and best developed in the gonal positions. The crests between the gonal areas are finely foveolate to scrabate and have a characteristic lacerate edge (Figs 10A, B). The cingulum is 6 µm wide. Paraplates 6c and 1c are displaced about 6 µm in the midventral area. Tabulation is indicated by septa except in the midventral area. Septa have not been observed in the sulcal field. Precingular archaeopyle formed by the loss of plate 3’’. Most specimens have a free operculum. Total diameter 49(60)69 µm [8 specimens measured]. Cingulum 5(6)7 wide [4 specimens measured]. Septa 10(12)14 µm high [8 specimens measured].
Remarks. Impagidinium hannahii sp. nov. differs from I. celineae Jan du Cheˆne, 1988 and I. patulum Wall, 1967 and I. antecarcerum, de Verteuil & Norris 1996 by having septa that are lacerate at the margin, gonally expanded and fovealate.
Age and distribution. Impagidinium hannahii FO is below the sampled section, but it occurs consistently up to the upper part of the early Paleocene radiolarian zone RP2 and is sporadic within radiolarian zone RP3 corresponding to an interval from ca 64.7–64.3 Ma. This species is common in uppermost Maastrichtian strata. It was identified from Branch Stream, Grey River, Mead Stream, mid-Waipara River and Tawanui Stream.