Rallus is a genus of wetland birds of the rail family. Sometimes, the genera Lewinia and Gallirallus are included in it. Six of the species are found in the Americas, and the three species found in Eurasia, Africa and Madagascar are very closely related to each other, suggesting they are descended from a single invasion of a New World ancestor. Three endemic South American species are endangered by habitat loss, and the Madagascan rail is becoming rare.