Thalos VII was the seventh planet in the Thalos system.
This planet was home to the Thalian chocolate mousse, a delicacy made from cocoa beans aged for four centuries. (TNG: "The Dauphin")
According to the Star Trek: Star Charts, on the star chart United Federation of Planets I, the Thalos system was located in the Alpha Quadrant. This was a trinary star system.