Algolians are a humanoid sentient species native to the planet Algol II in the Alpha Quadrant. They joined the United Federation of Planets in the 30th century. They gained an embassy on the Citadel in the 31st century.
The Algolians evolved on the planet Algol II. Around 10,000 BCE, they had developed an advanced civilization which collapsed for unknown reasons. Their species then entered a dark age of little technological development, and many of their great monuments and cities fell into ruin. However, the Algolians would eventually recovered, and by 2950 CE they had joined the United Federation of Planets. In 3036 CE they gained an embassy on the Citadel.