Leptocephalus is a genus that was used for species of larval eels, called leptocephali.

When first discovered, leptocephali were thought to be a distinct type of fish,[1] not an eel specie.

Because of this, the genus designation of Leptocephalus was used for a while for an unidentified leptocephali.

After it was known that these were eel larvae, it was identified to be part of a wastebasket taxon, but not anymore in the present classification system.

Examples of marine congrid larvae, found in the western Indian Ocean and the Red Sea that were named this way are listed below.