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Manumiella rotunda

Manumiella rotunda Wilson, 1988

Holotype: Wilson, 1988, pl.16, figs.3a–c; Fensome et al., 1996, figs.1–3 — p.2335.
Locus typicus: Hawkes Bay, New Zealand
Stratum typicum: Paleocene (Teurian)

Original description: Wilson, 1988, p. 26
Cyst of intermediate size, weakly circumcavate, occasionally bicavate, subcircular to slightly ovoidal. Apical pericoel poorly developed, antapical pericoel slightly longer. Apical horn not developed or represented by short protuberance (length up to 2 µm); antapical horns not developed. Periphragm thin, pale, smooth or finely reticulate. Endophragm fairly thick, dark coloured, finely reticulate. Archeopyle relatively broad, elongate, hexagonal; opening in pericyst and endocyst in close contact; operculum attached posteriorly. Paracingulum sometimes delineated by single transverse ridge or fold. Parasulcus not indicated. Paratabulation indicated only by archeopyle outline.
Dimensions: Holotype: overall length 81 µm, breadth 76 µm, length of endocyst 76 µm, breadth 70 µm. Range: overall length 65(72)83 µm, breadth 62(68)79 µm (n = 10).

Affinities:
Wilson, 1988, p. 26: The globular pericyst outline, narrow circumcavation, lack of well defined apical and antapical pericoels, and lack of horns help distinguish M. rotunda from other species of Manumiella. The species differs from superficially similar species of Deflandrea (e.g. D. truncata) in its archeopyle structure and from species of Nelsoniella, Xenikoon and Isabelidinium in generally being circumcavate rather than epicavate or bicavate.
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