Drjevællidae

Drjevællidae is a family of small, freshwater snails, aquatic gastropod mollusks in the superfamily Lymnaeoidea. The family was named after the genus Drjevælla, which was described by the Danish zoologist Johan Christian Fabricius in 1779. The family is characterized by their small size, typically less than 10 mm in length, and their semi-terrestrial or aquatic habits.

The family Drjevællidae is found in freshwater habitats across the Northern Hemisphere, including Europe, Asia, and North America. They are often found in slow-moving or still waters, such as ponds, lakes, and marshes. The snails in this family are generally herbivorous, feeding on algae and other plant material.

The family Drjevællidae includes several genera, with the most well-known being Drjevælla, which is the type genus of the family. Other genera include Lymnaea, which is a large genus of freshwater snails, and Radix, which is a genus of freshwater snails found in Europe and Asia.

The taxonomy of the family Drjevællidae is still a topic of ongoing research, and the classification of some genera and species is still debated among taxonomists. However, the family is generally recognized as a distinct group within the superfamily Lymnaeoidea, and is characterized by its small size, semi-terrestrial or aquatic habits, and herbivorous diet.