What is "rivulidae"

The Rivulidae are a family of killifishes in the order Cyprinodontiformes. They are commonly known as rivulids, South American killifish or New World killifish. The latter names are slightly misleading, however, as they are neither restricted to South America – though most are in fact found there –, nor are they the only killifishes from the Americas. Occasionally, they are still referred to as rivulines, a term dating back to when they were considered a subfamily of the Aplocheilidae.

The subfamilial name "Rivulinae" was already established for noctuid moths by Augustus Radcliffe Grote in 1895. That name, though it is the senior homonym, may be suppressed because the name Rivulinae for the fish subfamily is widespread, whereas the moth taxon is little used.

In the meantime the family-group name Cynolebiidae Hoedeman 1961 can be used for the family.