Difflugia bacillifera Penard, 1890
Diagnosis: test ovoid, flask-shaped or elongate with a distinct, long, cylindrical neck, not compressed, with a smooth fundus; neck variable in length; neck usually a little widened towards the aperture; shell mainly or completely composed of diatoms, which are sometimes scattered with sand particles or foreign bodies such as minute tests of siliceous flagellates or rhizopoda, e.g. Euglypha; shell usually transparent, light brown or yellow. Aperture circular.
Dimensions: length 117-194 µm, Penard mean 158 µm; Awerinzew 150-190 µm; Cash 145-160 µm; Jung 145-180 µm; Hoogenraad & De Groot 120-180 µm.
Ecology: Sphagnum pools and mosses. Not rare.
Remarks: Outline often masked by the diversity of diatom frustules that are incorporated into the structure, and in some instances the whole of the shell may appear to be an amalgamation of diatoms. The siliceous materials used vary from diatom frustules almost equal in length to the body of the shell, to small frustules about 10 um long, and spherical siliceous cysts of chrysomonad flagellates.