Mitrephora sirikitiae (Annonaceae): A remarkable new species endemic to northern Thailand
A new species of Annonaceae, Mitrephora sirikitiae, is described from Mae Hong Son Province in northern Thailand. It is easily distinguished from the seven species of Mitrephora previously recorded from Thailand due to its very large, showy flowers. It is most similar to M. winitii, but differs in its larger flowers, with inner petals that become undulate at maturity. The profuse blooming of the new species and its large flowers with mild fragrance suggest that may be of significant horticultural potential.