P. hausmannii – SEM photomicrograph Kenneth Dumack

Penardeugenia hausmannii  Dumack, Siemensma and Bonkowski 2018

Diagnosis: Similar to Penardeugenia huelsmannii with following differences: Cell body about 17.4 ± 2.4 µm in diameter (range 14 – 22 µm) and about 19.8 ± 3 µm long (range 17.2 – 22.5 µm). The upper scales of P. huelsmannii are flat, whereas those of P. hausmannii have a central depression, bordered by the three holes. The holes of the latter lie approximately at two thirds of the distance between corner and center. The holes of P. huelsmannii lie at about three fifth of that distance.

Dimensions: Plate-scale, 1.35-1.71 µm in diameter; distance between holes 0.21 and 0.57 µm. Spine-scales 6.18-7.80 µm long, excluding basal structure. Basal structure 0.78-1.01 µm in diameter. Shaft of the spine tapering from 0.30 µm above the upper basal plate to 0.18 µm below the sharply pointed apex.

Ecology: Aquarium sediment in the University of Cologne, Germany

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

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