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Genus Nebela

Shell is rounded, ovoid-pyriform, or wide-pyriform, rarely with a keel (partial or complete) or other lateral expansions, with or without wavy lateral margins. Aperture is ranging from linear to strongly curved, bordered by a more or less thin organic lip (rim, collar or fringe). Shell is hyaline or slightly yellowish, reinforced with circular to elongated shell plates apparently recycled mostly from euglyphid testate amoeba prey, sometimes also including fragments of diatom frustules or other small mineral elements. Type species: Nebela collaris (Ehrenberg, 1848) Leidy, 1879