Genus Schoenbornia Decloitre, 1964

 

Diagnosis: Shell ovoid, circular in cross section, hyaline, transparent, aperture circular (Fig. 82). Test composed of collected idiosomes of small euglyphids, angular quartz, and amorphous siliceous elements. Schönborn et al. (1987) suppose that the latter are produced by the amoeba, but this remains unproved. Large nucleus with central nucleolus, up to 3 contractile vacuoles, usually only 1 extended lobopodium. Resting stages spherical cysts with thick membrane separate from the shell wall and precysts with plasma retracted in the posterior part of the shell and covered with a thin membrane. Both stages have their aperture sealed with a diaphragm often hidden by a detrital plug.
Type species: Schoenbornia humicola (Schönborn, 1964).

 

Ecology: Acid moder and raw humus known from Europe, Africa, and Asia. Collects detritus with bacteria and stores it around the aperture.

 

Remarks: Two species. Ref. Coûteaux (1978), Schönborn et al. (1987). Heleoporella Coûteaux, 1978 is probably a synonym of this genus.

 

Its taxonomic position is not clear.