Вероятно, мы нашли категорию простейших по вашему запросу:



Genus Longinebela

Shell is elongated-pyriform, with a distinct neck, lateral margins (that can be straight or wavy) tapering towards the aperture. Shell is hyaline or slightly yellowish, composed of circular to elongated shell plates probably recycled from euglyphid testate amoeba prey. Type species: Longinebela tubulosa (Penard, 1902)