What is "abyssocottidae"

The Abyssocottidae are a family of fishes in the superfamily Cottoidea, the sculpins. They are known commonly as the deep-water sculpins. The entire family is endemic to Lake Baikal in Siberia.

Sculpins of this family live in deep water, usually below 170 m. There are 24 known species in seven genera. These include, for instance, Abyssocottus korotneffi and Cottinella boulengeri which are among the deepest-living freshwater fish. Baikal is the deepest lake on Earth (1642 m), and sculpins occupy even its greatest depths.