The Kneriidae are a small family of freshwater gonorhynchiform fishes native to sub-Saharan Africa. The species in this family typically live in fast-flowing streams, often in highlands, and are small fish, no more than 15 cm in length. The second subfamily Phractolaeminae contains only a single species, which typically inhabits stagnant or slow-moving waters and reaches up to 25 cm in length. All Kneriidae have an elongated body shape. Some species are sexually dimorphic, with the male possessing a rosette on the gill covers that is absent in the females. Other species are neotenic, retaining larval features into adulthood.

Classification

There are about 31 extant (living) species in four genera. Phractolaemidae is now regarded as a full family.

Genera

In addition, the family includes the genus Mahengichthys, which only is known from Eocene fossil remains and is closer to Kneriinae than Phractolaemidae.