Anguilliformes -

: Many species lack scales entirely; if present, they are deeply embedded in the skin. Diversity and Habitat

The most distinct feature of the Anguilliformes is their . After hatching as transparent leptocephali , they drift on ocean currents for months or years. They then transform into juvenile "glass eels" before reaching their adult form. anguilliformes

The oldest fossil record of a living true eel lineage ... - bioRxiv : Many species lack scales entirely; if present,

Anguilliformes is the taxonomic order of , a group of ray-finned fishes containing approximately 1,000 species across 20 families. They are defined by their elongated, cylindrical bodies and a unique life cycle involving a transparent, leaf-like larval stage called a leptocephalus . Key Biological Features They then transform into juvenile "glass eels" before

While many other fish—such as electric eels and swamp eels—have evolved similar elongated shapes, they belong to different taxonomic orders and are not "true" eels.

True eels are found globally in a vast range of aquatic environments:

: Most species have a snakelike appearance with a complete absence of pelvic fins . Their dorsal, anal, and caudal fins are often continuous, forming a single fringe around the tail.