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Penardeugenia
Elliptical aperture through which filopodia and conopodia extend

Genus Penardeugenia Deflandre, 1958

Diagnosis: Cells are flexible and covered with a thin sheath of scales which in light microscopy appear as a two-tiered layer that is usually adherent to the cell body. Individuals may or may not bear spines. Pseudopodia emerge from a highly flexible aperture. By far the most pseudopodia commonly point in the direction of movement (anterior), some are laterally directed, and only rarely some pseudopodia are pointed backwards. The pseudopodia are elongated, conical with a rounded tip, showing some resemblance to true filopodia. The nucleus is relatively large, apical, spherical, finely marbled when observed with DIC and contains one roundish, relatively small nucleolus in its center. No cysts or flagellated stages were observed.

Type species: Penardeugenia bathybioticus (Penard, 1904). Eugenia bathybioticus (homonym, was replaced by Deflandre (1958).

Ecology: herbivorous. Fresh water and soil, oligotrophic lakes, sediment, dry mosses.

Reference: Dumack, K., Siemensma, F., Bonkowski, M., 2018. Rediscovery of the Testate Amoeba Genus Penardeugenia (Thaumatomonadida, Imbricatea). Protist, 169, 1, 29-42.

Penardeugenia Weser
Flexible aperture (arrowheads)
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