Satyr
A satyr was a lifeform that could be found on the planet Megas-Tu. They were humanoid, with a furred lower half with tails and hooves, while the upper half was much like Humans', except for horns and a lack of nipples. Like other Megans, they were capable of using magic.

Lucien belonged to this species. In 2269, another young boy satyr suddenly appeared before James T. Kirk when Lucien took Kirk, Spock and Leonard McCoy to Megas-Tu, Lucien's homeworld.  ()

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Species