rivulid

Noun

 * 1)  Any fish in the family.

Usage notes

 * The name "Rivulidae" as applied to the fish family is technically invalid according to the, but historically the moth family that would have the name instead has been treated as a subfamily or tribe. Because of this, "rivulid" has been used only for the fish so far, though that could change. Since the fish name is much better established and more widely used, it's possible an exception could be made to let the fish family keep the name. No action has been taken as yet to change either the moth or the fish name, however.

Synonyms

 * New World killifish
 * South American killifish