Tunston

Tunstons are a sapient species of tiny slug-like creatures which usually employ giant robotic exosuits for locomotion, although they can also parasitically inhabit the bodies of other life forms.

Biology
Tunstons are tiny green gastropods with tendrils and appendages on their backs. The exact number of appendages varies from individual to individual. They have three red eyes and a tubular mouth with needle-sharp teeth.

This species seems to have evolved as parasites, since they can be safely swallowed by other life forms and will migrate to the host's brain, where they can assume full control of the host for limited time periods. When the host isn't being controlled, it seems to retain no memory of its actions during such periods.

When inhabiting their robotic exosuits, Tunstons remain suspended inside a green fluid which presumably contains the same environmental requirements that they would normally get from a living host.

Culture and society
Tunstons are a hostile species bent on invading other worlds and conquering them by releasing clouds of bacterial ooze. They're ruled by a king. In normal circumstances, they employ robotic exosuits, which they consider preferable to inhabiting biological hosts, presumably due to the fact that a host can only be controlled for limited periods.

Appearances

 * Men in Black: The Series, s03e39, "The Bad Doggie Syndrome" (2000)