Heleopera sordida Penard, 1910

Diagnosis: Shell strongly compressed, with a very regular obovate outline, abruptly cut in front of a wide truncated elongated slit aperture. Shell transparent, of a very light dirty yellow; smooth, without the appearance of scales or reticulations; here and there and especially behind, covered with xenosomes, and stained with brown or blackish particles, of organic origin, which most often even replace here the siliceous flakes characteristic of Heleopera in general. The plasma, gray, is differentiated into an anterior region where food accumulates, and a posterior lighter region, which contains the nucleus, very large, and of a structure conforming to that of the other species of the genus, i.e. representing a mass grayish, compact, pasty, in which small rounded nucleoli are disseminated without order. Pseudopodia relatively narrow and numerous.

Dimensions: Length 60-70 µm, average 66 µm.

Habitat: Sphagnum

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