Family Cryptodifflugiidae Jung, 1942
Diagnosis: Surface organic or with attached mineral particles. Aperture terminal or eccentric.
Three genera:
Genus Cryptodifflugia Penard, 1890
Shell smooth, clear, flask- or egg-shaped, circular in cross-section, with adhering foreign particles or smooth surface; nucleus vesicular; cyst in test, by mucous plug.
Genus Meisterfeldia Bobrov, 2016
Ovoid shell, which is bilaterally symmetrical and laterally compressed, composed of proteinaceous material without mineral particles; circular sub-terminal aperture placed on ventrally and obliquely cut apertural end, or it is situated on a well developed or poorly expressed neck inclined ventrally
Genus Wailesella Deflandre, 1928
Shell brown, aperture eccentric. Shells superficially remember Trinema shells.