Additions to the Vietnamese species of Magnolia L., sect. Gwillimia DC. (Magnoliaceae)

Magnolia champacifolia J. E. Dandy ex F. Gagnepain, sp. nov., originally described, but invalidly published in 1938, is validated here by designating the flowering sheet as the holotype. Otherwise, a new species of Magnolia L., M. lamdongensis V.T. Tran, N.V. Duy & N.H. Xia, sp. nov. from southern Vietnam is described and illustrated. It is distinguished from the closely related M. champacifolia J. E. Dandy ex F. Gagnepain, sp. nov., and M. albosericea Chun & Tsoong by its leaf blades narrowly ovate, glabrous, apex long acuminate, petiole c. 3 cm long, tepals short and glabrous, peduncle c. 3 cm long and densely papillate when young, and gynoecium glabrous.