In Star Trek: The Next Generation, season 1 episode 25, 'Conspiracy', there were aliens
who are an insect-like parasite that controls the body of whomever it enters.
What species was this alien?
Also, was the alien related to the creatures from Ceti Alpha, used by Kahn to control Chexkov and Captain Terell?
They never appear again or recieve an official name in Star Trek canon.
In noncanoncial sources sources, however, they are named Bluegills or are simply called Parasites and are closely related to (and in some sources, genetically engineered from) Trill Symbionts (and therefore not related to the Ceti Alpha V creature, as long as we assume that it was truly indigenous to the planet as Khan claimed).
So the answer to your question really depends on which books you read.
