Infraorder Excentrostoma Lahr et al., 2019

Diagnosis: Shells compressed in the axis perpendicular to the aperture (“dorso-ventrally compressed”). Aperture off-center.

Remarks: This group comprises many species adapted to soils, especially forest litter. The lateral (“ventral”) position of the aperture has been considered an adaptation to dry environments. Further invagination of the aperture is likely to protect the organism from drought even more efficiently.

Type Family: Centropyxidae Jung 1942