Difflugia manicata  Penard, 1902

Diagnosis: Shell ovoid, covered with neatly arranged mineral grains. A broad region (1/3 of the shell) of the anterior part of the shell is covered with much larger particles. Aperture small and circular. Nucleus with central compact nucleolus with small lacunae.

Dimensions: Penard (1902): Shell length 60-88 µm, width 37-54 µm, apertural diameter 12-20 µm, nucleus 13 µm.

Ecology and distribution. Freshwater. In sediment. Switzerland.

Difflugia manicata var. langhovdensis Sudzuki, 1964

Diagnosis: Shell constantly pyriform, slightly compressed and the posterior end more or less pointed. With a rounded posterior border in the lateral view. Aperture circular, without neck. Mineral particles concentrated around the aperture, very rarely or never at the posterior half of the shell, except for the mineral particles. Protoplasm usually located at the posterior half of the body, and in the cyst very often wholly spherical in form, away from the shell. Nucleus, one in number.  The present species is much like D. lucida, D. fallax and D. pristis in general features and size, but different in lacking the remarkable ridge usually present around the aperture, and the lateral outline of the shell (parallel in D. lucida) from the first, different in the condition of the large mineral particles attached from the second, and different in the nature of the material stuck to the shell from the third.
The present species could be identical with D. manicata Penard, but clearly different from its type by its having a compressed shell.

Dimensions: Sudzuki (1964): Shell length 55-62 µm; width 19-32 µm; thickness 20-25 µm; aperture 29 x 19 µm.

Ecology and distribution. Moss, Langhovde, Antarctica,

Remarks: Probably this variety is identical with Heleopera lucida.