About 115 species in about 9 genera are known chiefly from the Oriental and Afrotropic biogeographic regions with one lineage in the New World.

The scutellum is enlarged, and forming a protective shell over the abdomen, giving them a beetle-like appearance.

The family name is derived from the Greek word κέλυφος for pod or shell.

Male celyphids lack an aedeagus and instead have paired gonapophyses that are used in copulation and are of key taxonomic value.

Adults are found along streams and rivers, and in wet, grassy areas.