What is "hygrobia"

Hygrobia is a genus of aquatic beetle native to Europe, North Africa, China and Australia. It is the only genus in the family Hygrobiidae, also known as the Paelobiidae. These are known commonly as squeak beetles and screech-beetles.

There are six known living species: H. australasiae , H. davidi, H. hermanni, H. maculata, H. nigra, and H. wattsi, the latter having been described only in 2010.

One species is extinct: H. cretzschmari.