Leptocephalus is a term used to describe the flat and transparent larval form of eels. These creatures are characterized by their elongated bodies, small heads, and lack of scales. Synonyms for leptocephalus include the term "ribbon eel," which refers to the long and slender shape of the larva. Other synonyms include "glass eel," "elver," and "slippery eel," which all describe different stages of eel development. These synonyms are often used interchangeably and are important for understanding the life cycle of eels, which have long been shrouded in mystery due to their elusive nature and unique life history.