Cetopsidium

Cetopsidium is a genus of freshwater ray-finned fishes belonging to the family Cetopsidae, the whale catfishes. The fishes in this genus are found in South America.

== Taxonomy == Cetopsidium was described in 2005, its name coming from the Cetopsis, the first described cetopsid genus, and idium which means diminutive, in reference to the relatively small size of Cetopsidium species. Three existing species were transferred to this genus and three new species were described. In 2009 a new species, Cetopsidium soniae, was described bringing the number of species in the genus to seven.