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Saccamoeba wellneri - Ferry Siemensma
Saccamoeba wellneri

Saccamoeba wellneri Siemensma, 1987

Diagnosis: Locomotive form behavior and form typical of genus, with shallow hyaline cap in locomotion; locomotion slightly sigmoid; nucleus with central globular nucleolus; crystals crescent-shaped, with a thickened central area; uroid often a papillated bulb; contractile vacuole slightly bulging at the posterior end.

Dimensions: 96-130 µm; nucleus 12-21 µm.

Ecology: freshwater, Europe; several water types, both polluted and mesotrophic.

Remarks: The most remarkable feature of this species is the bilaterally symmetric shape of the crystals, resembling a “croissant”, a French roll.

The name “wellneri” refers to my friend Rob Wellner, who introduced me into the world of protists.

Literature: Siemensma, 1987, Mrva, 2007.

Saccamoeba wellneri
Saccamoeba wellneri
Saccamoeba wellneri
The very characteristic croissant-shaped crystals.
Saccamoeba wellneri - Ferry Siemensma
Saccamoeba wellneri, with nucleus and crystals
Saccamoeba wellneri - Ferry Siemensma
Saccamoeba wellneri
Saccamoeba wellneri
Saccamoeba wellneri, after Mrva, 2007
Saccamoeba wellneri
Crystals and uroid
Saccamoeba wellneri
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