Semi-slugs, also spelled semislugs, are land gastropods whose shells are too small for them to retract into, but the shell is not quite vestigial. The shell of some semi-slugs may not be easily visible on casual inspection, because the shell may be covered over with the mantle.
Semi-slugs from the Neotropics:
- family Amphibulimidae: Amphibulima and Gaeotis
- family Xanthonychidae: Cryptostrakon, Semiconchula and Xanthonyx
- family Pleurodontidae: Coloniconcha prima
- Semi-slugs do exist but are exceptional in the Camaenidae.