Odostomia is the most speciose genus of minute sea snails, pyramidellid gastropod mollusks. This genus is placed in the family Pyramidellidae in the subfamily Odostomiinae. There are several hundred species in this diverse genus (Schander et al. 1999) Most of the description of species in the genus Odostomia was carried out by Dall & Bartsch in 1909. Many of the described species are however suspected of being synonyms, or are proven synonyms.