Argynnia teres Jung, 1942

Diagnosis: Pseudostome always circular. The plates forming the lip are large, few in number and protrude laterally like a crown-like bulge. The covering is made up of scattered thicker pieces of pebbles. The outlines are sometimes slightly asymmetrical. Distinguished from all representatives of the genus by its extremely slight flattening.

Dimensions: Length 98-109 µm; width 53-68 µm; aperture 20-27 µm; slight flattening: 1/7 of the width.

Habitat: Freshwater. Sediment of waterfall mosses and forest stream mud.