Ellipsopyxis arcuata Bonnet, 1977

Diagnosis: Shell brownish, oblong in dorsal and ventral views. Ventral sole well differentiated and very clearly curved. In lateral view reniform. Large elliptical pseudostome with weak invagination. Shell wall very transparent and very thin, yellowish-beige in color, embedded with very regular and closely juxtaposed siliceous platelets.

Dimensions: Average length 64.8 µm, SD 5.1 µm; width 31 um, SD 5.3 µm; pseudostome 31 X 24 µm (n=5).

Ecology: Humiferous soil, Orizaba forest, Mexico.