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Genus Microcorycia

Shell is flexible and comprised of two parts: upper and lower. The upper shell part is dome-shaped, sometimes with concentric ridges or small horns at the dorsal side; thick and less flexible walls than the lower shell part; maybe covered with small debris or mineral particles. The lower shell part consists of a thin, transparent skin, which shows no structure in the light microscope, can be folded up and is open downwards for extruding pseudopodia. The skin only loosely covers the cell body and can be contracted like a sack. There is a zone of gradual transition from the upper shell part to the lower shell part. Ecology: mosses, soils, freshwater. Type species: Microcorycia flava (Greef, 1866) Penard, 1902