Fyrrispurninnidae

Fyrrispurninnidae is a family of small, freshwater snails, aquatic gastropod mollusks in the superfamily Lymnaeoidea. The family is native to the Northern Hemisphere, with species found in Europe, Asia, and North America. The family was first described by the Danish zoologist Johan Christian Fabricius in 1779.

The family includes two genera, Fyrrispurninnus and Fyrrispurninnus, both of which are small, semi-aquatic snails with a thin, translucent shell. The shells are typically ovate or oval in shape, with a smooth surface and a single, open spire. The family is characterized by its unique reproductive strategy, in which the male snail transfers sperm to the female using a specialized organ called a penis retractor.

Fyrrispurninnidae is an important group of freshwater snails, playing a role in the ecosystem as both predators and prey. They are also of interest to scientists studying the evolution of reproductive strategies in mollusks. However, the family is not well-studied, and much remains to be learned about its biology and ecology.