Lumbriculidae

The Lumbriculidae are a family of microdrile oligochaetes common in freshwater environments, including streams, lakes, marshes, wells and groundwater. They should not be confused with the earthworm family Lumbricidae. Many species and genera are highly endemic, mainly in Siberia and the western parts of North America. Lumbriculidae are the only family in the order Lumbriculida.

Stylodrilus is a genus of annelids belonging to the family Lumbruculidae.

Rhynchelmis is the genus of 26 species of aquatic oligochaetes from the Northern Hemisphere, with 14 species from North America and 12 from Eurasia. They are part of the family Lumbriculidae, which are among the largest of the microdriles. They are generally defined as having atria in segment X and spermathecae in segment VIII. The prostomium generally has a proboscis, from which the genus has got its name.