Difflugia praestans
D. praestans, 343 µm (Naardermeer, Netherlands)

Difflugia praestans Penard, 1905

Diagnosis: shell slightly yellow, large, long and straight, tubular, not compressed; fundus rounded with a short sharp spine or sometimes with two short spines. Nucleus vesicular, spherical, with one large central homogeneous nucleolus.

Dimensions: Length 350 – 420 µm (average 375 µm).

Ecology: Fresh water; sediment of deep waters.

Difflugia praestans
Difflugia praestans, Pénard Collection, Geneva – Photograph by Thierry Arnet, as part of the Pénard project.
These shells were prepared by Penard and labeled as “Difflugia praestans” (image from Mazei and Warren, 2012). Is it a separate species or just a variation?

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