The humanoid population of the Federation world Ardana, split between the cultured elite of the floating city Stratos and the Troglytes who toil in the zenite mines on the surface below.
The Ardanans appear in the Original Series episode The Cloud Minders. Their planet is the only known source of zenite, a mineral the Enterprise urgently needs in 2269 to stop a botanical plague on Merak II.
Ardanan society is rigidly divided. The city-dwellers live among the clouds in Stratos, devoting themselves to art and thought, while the Troglytes mine zenite and are denied education and a place in the city. The council, led by High Advisor Plasus, insists that Troglytes are naturally inferior. A resistance movement, the Disruptors, led by Vanna, has begun to fight back.
McCoy discovers that raw zenite gives off an invisible gas that dulls the mind and inflames the temper. Kirk proves it by trapping himself, Plasus and Vanna in a mine, and the Troglytes win filter masks and the beginning of a negotiation. Plasus's daughter Droxine is drawn to Spock.