Heleopera – Microworld

Heleopera petricola var. amethystea – stacked image

Genus Heleopera Leidy, 1879

Diagnosis: shell always laterally compressed; aperture terminal, lenticular or slit-shaped, with a thin but distinct organic rim; colorless or yellowish, but with reddish or purple species; test composed of collected euglyphid body plates, mineral particles or diatoms, these materials often coated and reinforced with siliceous material; nucleus ovular.

Habitat: Freshwater sediment, mosses (Sphagnum) and soil.

Key to the species:

1	Shell colorless or yellowish to brownish yellow	2
–	Shell wine red to purple red or purple	3
2	Shell yellow to brown yellow, hardly covered with xenosomes; protoplasm with zoochlorellae	H. sphagni
–	Shell colorless, usually covered with many xenosomes	H. petricola
3	Shell wine red, with yellow lip	H. rosea
–	Shell purple red to purple, without yellow lip	H. petricola var. amethystea