Cryptodifflugia crenulata, division; right hand cell with very large crystal

 

Cryptodiffflugia crenulata Playfair, 1917

Diagnosis: shell ovoid, with truncate base, above which it is sometimes slightly constricted to form an obscure neck, end-view circular, crenelated; membrane smooth, thick, chitinous, hyaline or pale yellow, indented all over so as to appear broadly crenelated in optical section, both front and end; aperture circular, simple, slightly smaller than the base. Nucleus spherical. Cell sometimes with one or two large bipiramidal crystals.

Dimensions: Playfair length 17-20 µm, breadth 14-16 µm; my measurements 15-18 µm.

Ecology: Fresh water, on waterplants. Not rare.

One long pseudopodium
Cryptodifflugia crenulata
Cryptodifflugia crenulata
Specimen with nucleus and crystals and specimen with two crystals and a pseudopodium
Cryptodifflugia screnulata
Cryptodifflugia crenulata
Shell 15 µm and 18 µm
Cryptodifflugia crenulata
Cryptodifflugia crenulata

Shell 30 µm, Lolo Pass USA

Cryptodifflugia crenulata

Drawing after Playfair; to the left var. globosa
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