Heleopera sphagni Leidy, 1874

Diagnosis: Shell broadly ovoid, regular in outline, compressed; chitinous membrane tinted yellowish (rarely brownish), with a surfacing of irregular transparent siliceous plates; fundus with little foreign material, often without. The presence of the chlorellae seems to be necessary to the life of the animal.

Dimensions: Length 87-168 µm; my measurements: 115-128 µm (Sweden).

Habitat: Sphagnum swamps.

Remarks: Heleopera picta is a synonym for H. sphagni.