Difflugia claviformis
Difflugia claviformis, front and side view, 424 µm

Difflugia claviformis (Penard, 1902)

Diagnosis: test pyriform, compressed, with a distinct aboral protuberance, colorless, composed of small to large pieces of quartz; pseudostome surrounded by small particles.

Dimensions: Penard (1902) 380-450 µm; my measurements: 380-434 µm.

Ecology: In sediments of ditches.

Remarks: Shells of Difflugia claviformis seem to be rare. I found this species only in the sediment of a ditch in the nature reserve Naardermeer in the Netherlands. I am not convinced that this is a separate species. I always found it together with specimens of Difflugia nodosa. Probably both species are identical. Further records are necessary.

Difflugia claviformis
Tests 412 and 403 µm high; Naardemeer, Netherlands.

I’m not convinced that the species below belong to D. claviformis.

Difflugia claviformis
Shells 461-448 µm, stacked image. I found this large en remarkable shells in sediment of a small mountain lake near Lolo Pass, Montana USA. It differs from every shell I’ve seen before. One shell was symmetrical and the other asymmetrical.
Difflugia claviformis
Difflugia claviformis
Pseudostome and neck
Difflugia claviformis
Difflugia claviformis
The same Difflugia compared with some other species in the same sample from Lolo Pass, 98-461 µm.
Difflugia claviformis
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