Ceti eel

The Ceti eel was a lifeform native to the planet Ceti Alpha V.

The Ceti eel utilized a creature known to Khan Noonien Singh and his followers as the "Ceti bison" as a host for its young. The young would wrap themselves around the animal's cerebral cortex which would result in changes in the bison's behavior as the eel grew in size. At times the Ceti bison could appear inactive, while at other times, they seemed to stagger and move about in an odd, almost drunken, manner. Fortunately, as the two creatures had evolved on the same planet, the Ceti bison did not suffer any ill-effects from acting as host.

When Ceti Alpha VI exploded in 2268, shifting the orbit of Ceti Alpha V, the planet went from being Class M to Class K; all life on the planet died except for the Augment colonists and the Ceti eel. In fact, the eel survived by turning to the colonists to serve as its new host. Several of Khan's followers, including his wife, Marla McGivers, died after being infected with the eel.

In humans, the eel rendered its victims highly suggestable. Unfortunately, as the eel grew size, individuals would begin to experience fits of madness and eventual death.

In 2285, when the USS Reliant visited Ceti Alpha V seeking a suitable planet on which to deploy the Genesis Device, Captain Clark Terrell and Commander Pavel Chekov beamed down to the surface to check some unusual readings. The two men came across the Botany Bay colony and were subsequently captured by Khan who had eels placed into their ears to make them more suggestable and reveal why they had come to the planet. (Movie: Star Trek II: The Wrath of Khan and Decipher: Worlds).