Copelatus is a large genus of small diving beetles.

There are some 470 described species in the genus, found worldwide, but they are most diverse in tropical South America, Africa and South-East Asia.

Copelatus are often black or brown in color, many species of Copelatus possessing visible longitudinal furrows down the dorsal side of the wings of both sexes.

[2] The genus Copelatus is divided into several subgenera (Colepatus, Papuadytes etc.

It may be paraphyletic with respect to the smaller Copelatinae genera Lacconectus and Aglymbus.