Lyonothamnus

Lyonothamnus is a genus of flowering plants in the Rosaceae family containing only one species: Lyonothamnus floribundus. Members are native to the Channel Islands of California.

Lyonothamnus is currently a geographically island endemic genus containing only one species with two subspecies. However, fossil studies suggest that the genus once comprised of several species, all but one now extinct, which had grown on the mainland of the United States.