Corythion dubium var. gigas Thomas, 1953
Diagnosis: shell ovoid, composed of oval shell-plates, irregularly arranged, very small and usually overlapping each other; aperture sub-terminal, oval and invaginated.
Dimensions: Length 76-90 µm; breadth 34-42 µm; mouth 14-18 µm.
Ecology: Sphagnum and mosses.
Remarks: This variety strongly resembles Trinema enchelys, but differs in the shape of the plate scales.