Microgromia longisaepimen De Saedeleer, 1934
Diagnosis: Shell hyaline, usually irregular in outline, with one side fastened to the substrate; shell clearly asymmetrical with a distinct and long septum. Neck usually short and small. Septum well developed. Cytoplasm asymmetrical, with a bundle of pseudopodia (Pseudopodienstiel). Pseudopodia granular, very thin, and branching. Nucleus relatively large, globular with a central nucleolus. One contractile vacuole.
Dimensions: De Saedeleer (1934): shell 17.0-18.7 µm, nucleus 6.8 µm. Kreutz (2012): 12-21 µm, nucleus 6.2-6.9 µm.