Another fleetingly-seen alien from Star Trek: The Motion Picture is the Megarite, an aquatic species with four lips and thick hide. It has an interesting backstory, where they could only leave their planet by using intravenous injections to provide nutrients. Their lips allow them to sing unique poetic songs. Their planet also has vast quantities of jade, which is used as tools and in structures throughout Megarite society.
As aquatics, they may be good additions to the Poseidonis module.
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