The Tholian Assembly

Tholians are a starfaring and extremely territorial race in the Star Trek fictional universe. The Tholian ( ) home nation is the Tholian Assembly, which inhabits an area of space in the Alpha Quadrant, near the Cardassian Union and the Badlands.

The Tholian Assembly is located in a region of space bordering the southern parts of the Klingon Empire and the United Federation of Planets. Tholia, their homeworld, is a Class Y planet.

Non-humanoid in form, Tholians have crystal bodies, two arms, and six legs. They dwell in an environment of extreme heat by human standards, their comfortable living environment being 480 kelvin (207 °C). Temperatures below 380 K (107 °C) will kill Tholians, causing them to shatter into tiny crystalline shards. Each Tholian has both male and female sexual organs.

Natural Tholian speech is a series of shrill squeals and clicks, similar to the sounds of a dolphin. Their speech is difficult to pass through the universal translator.