The Chessu were a warp-capable species from the Delta Quadrant. They resided in a region of space also occupied by the Antarians, the Aksani, the Terrellian, the Imhotep, and others.
Two Chessu ships participated in the Antarian Trans-stellar Rally of 2377. Ambassador O'Zaal had promised the hosting of the post-race ceremony to the Chessu, which caused protests by the Aksani. (VOY: "Drive")