A species able to shift between a human-looking form and a gray-scaled true form that can withstand extreme pressure, intense cold and brief exposure to open space.
The Khionians are a species from the world Khionia who can appear outwardly identical to humans. Their true form is hairless and covered in gray scales, with dark eyes.
This natural form is remarkably tough. According to the Khionian cadet Darem Reymi, introduced in Kids These Days, it allows him to withstand enormous pressure differences and temperatures close to absolute zero, and to survive in the vacuum of space for as long as eight minutes. Darem is one of the cadets attending Starfleet Academy in the thirty-second century.