Ciatella (or Iota Leonis) is a star system in the Tau Ceti Quadrant, made up of the binary stars Argelius A and Rho Magnin (Argelius B), and is the location of the planet Argelius II. (TOS novel: "Battlestations!") The primary is a yellow star. (The Worlds of the Federation)

The system has ten planets.(The Worlds of the Federation)