Difflugia humilis – after Chardez, 1991

Difflugia humilis Chardez, 1991

Diagnosis: Shell elongated or oval, in cross section more or less circular, hyaline, sides tapering towards the pseudostome, with a more or less clear neck or abruptly cut off, without a neat neck. Pseudostome circular, often irregular in shape. Shell composed of organic material, mainly covered with diatoms, giving it an irregular appearance. Cytoplasm clear, finely granulated, usually with one single pseudopodium. Nucleus spherical.

Dimensions: Length 40-60 µm (mean 47 µm, n=10), diameter 22-36.5 µm, pseudostome 8-15 µm, nucleus 9.5-10 µm. My measurements 33-49 µm.

Ecology: Freshwater. Sediment of ditches, Sphagnum. Ireland, Belgium, The Netherlands.

Remarks: The covering with diatoms can’t be a diagnostic characteristic, as stated by Chardez. It depends upon which material is available.

Difflugia humilis, 49 µm
Difflugia pulex
Difflugia pulex
Difflugia humilis, 33 µm – Naardermeer
After Chardez, 1991
Difflugia humilis, 49 um, Neer, Netherlands
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