Physochila stepaneki Laminger, 1973

Diagnosis: Shell fundus has several processes of different lengths. The shell narrows towards the aperture and forms a collar, the sides of which widen too much towards the pseudostome. In plan view, the strongly developed pseudostome collar is broadly oval, sometimes almost circular. Shell usually covered by larger and smaller mineral particles.

Dimensions: Length 71-82 µm, width 56-65 µm, pseudostome 39-47 µm, neck length 9-17 µm, neck width 23 µm, processes 9-30 µm.

Habitat: Freshwater, sediment, Mexico.