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Hystrichokolpoma truncatum
Hystrichokolpoma truncatum Wilson, 1988
Name illegitimate — senior homonym: Hystrichokolpoma truncatum Biffi and Manum, 1988 (September). Substitute name: Hystrichokolpoma wilsonii.
Originally Hystrichokolpoma truncatum Wilson, 1988 (name illegitimate), subsequently (and now) Hystrichokolpoma wilsonii.
Holotype: Wilson, 1988, pl.11, figs.1a–c; Fensome et al., 1996, figs.1–3 — p.2449.
Locus typicus: Waipawa Section, Hawkes Bay, New Zealand
Stratum typicum: Middle Eocene (Porangan)
Original descripion: Wilson, 1988, p. 22
Cyst small to intermediate, subspherical, bilayered, bearing short hollow, box-like intratabular processes. Precingular and postcingular processes very broad, polygonal, short (length to breadth ratio less than 1:2) with flat, closed distal extremities and a crenate or denticulate margin. Apical process slightly longer than others and somewhat more pointed; antapical process very broad, with a rounded tip. Paracingular and parasulcal processes short and narrow. All processes may have a small number of short spines at the tip (length 1-2 µm) and bases sometimes surrounded by irregular penitabular thickening. Periphragm surface smooth between processes and closely appressed to smooth endophragm. Archeopyle large with a slightly zig-zag margin and shallow sulcal notch.
Dimensions: Holotype (complete specimen): overall length 73 µm, breadth 54 µm, length of endocyst 54 µm, breadth 49 µm, length of apical process 14 µm, antapical process 8 µm, other processes 6-8 µm. Range: overall diameter 44(52)59 µm, diameter of endocyst 37(44)50 µm (n = 10).
Affinities:
Wilson, 1988, p. 22: This species differs from other species of Hystrichokolpoma in the nature and relative size of its processes. In particular the processes are usually somewhat shorter than those of H. spinosum Wilson (this bulletin) and have a crenate or denticulate rather than a spinose tip. Hystrichokolpoma mentitum McLean (1974) has similarly short processes which differ from those of H. truncatum Wilson (this bulletin) chiefly in their distal ornament.
Name illegitimate — senior homonym: Hystrichokolpoma truncatum Biffi and Manum, 1988 (September). Substitute name: Hystrichokolpoma wilsonii.
Originally Hystrichokolpoma truncatum Wilson, 1988 (name illegitimate), subsequently (and now) Hystrichokolpoma wilsonii.
Holotype: Wilson, 1988, pl.11, figs.1a–c; Fensome et al., 1996, figs.1–3 — p.2449.
Locus typicus: Waipawa Section, Hawkes Bay, New Zealand
Stratum typicum: Middle Eocene (Porangan)
Original descripion: Wilson, 1988, p. 22
Cyst small to intermediate, subspherical, bilayered, bearing short hollow, box-like intratabular processes. Precingular and postcingular processes very broad, polygonal, short (length to breadth ratio less than 1:2) with flat, closed distal extremities and a crenate or denticulate margin. Apical process slightly longer than others and somewhat more pointed; antapical process very broad, with a rounded tip. Paracingular and parasulcal processes short and narrow. All processes may have a small number of short spines at the tip (length 1-2 µm) and bases sometimes surrounded by irregular penitabular thickening. Periphragm surface smooth between processes and closely appressed to smooth endophragm. Archeopyle large with a slightly zig-zag margin and shallow sulcal notch.
Dimensions: Holotype (complete specimen): overall length 73 µm, breadth 54 µm, length of endocyst 54 µm, breadth 49 µm, length of apical process 14 µm, antapical process 8 µm, other processes 6-8 µm. Range: overall diameter 44(52)59 µm, diameter of endocyst 37(44)50 µm (n = 10).
Affinities:
Wilson, 1988, p. 22: This species differs from other species of Hystrichokolpoma in the nature and relative size of its processes. In particular the processes are usually somewhat shorter than those of H. spinosum Wilson (this bulletin) and have a crenate or denticulate rather than a spinose tip. Hystrichokolpoma mentitum McLean (1974) has similarly short processes which differ from those of H. truncatum Wilson (this bulletin) chiefly in their distal ornament.