New Xindus was a Federation class M planet in the Celes sector and the new homeworld of the Xindi species in the 24th century. (TNG - The Sky's the Limit short story: "Meet with Triumph and Disaster", ST reference: Stellar Cartography, STO video game: Star Trek Online)
History
Until 2154, the the star system of the future home for the Xindi lay inside the Delphic Expanse. The expanse was dissolved in that year. (ST reference: Stellar Cartography)
In 2311, New Xindus became a member of the Federation. (ST reference: Federation: The First 150 Years)
New Xindus was marked on a map depicting highlights of Federation history, made by Doctor Geoffrey Mandel, published in 2386. (ST reference: Stellar Cartography)