The Algolians were a humanoid species native to the Alpha or Beta Quadrant. By the 24th century, they were members of the United Federation of Planets.
In 2366, they attended the Trade Agreements Conference on Betazed. (TNG: "Ménage à Troi")
In 2367, an Algolian had a seat on the Federation Archaeology Council and attended the symposium on the USS Enterprise-D. (TNG: "Qpid")