Taxonomic revision of Magnolia section Maingola (Magnoliaceae)

Magnolia section Maingola Dandy is distinguished from other members of Magnoliaceae by the combination of a terminal brachyblast, cylindrical fruits, and free stipules. Morphological characters were re-examined for section Maingola and section Alcimandra, which has been considered to be closely related to the former. Although section Alcimandra is separated from section Maingola in having long stamens which hide the gynoecium, it is combined with section Maingola because this feature is frequently found in various other taxa of the family. Moreover, recent molecular phylogenetic studies have also demonstrated the close affinity between sections Maingola and Alcimandra. For the Magnolia macklottii complex, which has been problematic due to the wide range of variation in taxonomically important characters, a principal component analysis was carried out for 28 characters. Two varieties, M. macklottii var. macklottii and var. beccariana, are recognised in the complex. They are distinguished from each other mainly by hairs on fruit and peduncle (glabrous (to glabrescent)/densely hairy). Hairs on the twig, the length of scars of perianth and stamens, and leaf shape, which were previously regarded as important characters, could not separate the two varieties. In this study, seven species with five varieties are recognised in section Maingola.