Maiden rocksnail explained

The maiden rocksnail, scientific name †Leptoxis formosa, was a species of freshwater snail with a gill and an operculum, an aquatic gastropod mollusk in the family Pleuroceridae.

This species was endemic to the United States. It is now extinct.

References

• Lea, I. (1860). Descriptions of fourteen new species of Schizostomae, Anculosae and Lithasiae. Proceedings of the Academy of Natural Sciences of Philadelphia. 12: 186-188 [after 22 May 1860]., available online at https://www.biodiversitylibrary.org/page/26297333