Eel

Eels are multiple species of elongated fish which inhabit Earth and other planets. On Earth, they can be found in both oceanic and freshwater environments. Some, such as the electric eels and lamprey eels; are not biologically related to "true eels", which are members of the order Anguilliformes.

Many alien species resemble and/or are identified as eels.

Sapient eels:
 * Anguilla
 * Dur Sabon
 * Europan (Losing Mars)
 * Uteen

Non-sapient eels:
 * Aldebaran Eel
 * Armored Eel
 * Ceti Eel
 * Ion Eel
 * Keelkana
 * Lava Eel
 * Mon Calamari Eel
 * Osmotic Eel
 * Rishi Eel
 * Saberjowl
 * Skaro Electric Eel
 * Unidentified Creature from The Waters
 * Unidentified eel-like creature (Lost in Space)