Neural parasite
A neural parasite was a lifeform that attached itself to the nervous system of a host. There have been several different species encountered by the Federation that fell under this category.

 In 2154, the Xindi-Reptilians used a neural parasitic species to brainwash Hoshi Sato. ()
 In 2267, the  encountered a flying parasite at the Deneva colony. ()
 In 2364, the  encountered a species of parasitic beings attempting to infiltrate Starfleet Command. ()
 In 2380, Ensign Brad Boimler was infested by a neural parasite that Beckett Mariner termed a "googa". ()

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Lifeform classifications