Centropyxis gauthieri  Thomas, 1959

Diagnosis: Shell globular or oval in apertural view; no clear separation between ventral plane and visor. The ventral side invaginates the shell in an inclined plane, limiting, in its height, the opening of the pseudostome. In lateral view, the shell is quite swollen; its height corresponds to approximately half of the diameter. The ventral wall penetrates up to 3/5 of the total height. This wall is inclined and ends at its point of termination in a rounded cavity. The upper edge of the visor curves inwards. The shell wall is formed of a mixture of xenosomes intertwined with plant debris, more or less browned by the organic cement.

Dimensions: Length 53-65 µm; width 53-64 µm; height 35-38 µm; pseudostome infinitely variable in its opening.

Habitat: Thomas found it in large quantities in a moss on humic, acidic soil (pH 4.5) of a Maple head, at Branlac, Gradignan (Gironde), France.