Re-evaluation of the identity of Musa sabuana and Musa balbisiana var. andamanica (Musaceae), based on morphology, anatomy, seed micromorphology and molecular phylogeny

The identity of Musa sabuana and M. balbisiana var. andamanica are re-investigated here using integrative taxonomic approaches. Most recently, these two taxa have been treated as synonyms of a broadly defined M. balbisiana. The present study is based on a comparative morphology, foliar anatomy, seed micromorphology and anatomy, and molecular phylogeny (using nuclear ITS, chloroplast trnL–trnL–trnF and rps16). Musa sabuana and M. balbisiana showed remarkable differences in phyllotaxy, the shapes of the leaf bases and fruits, the thickness of their lamina, the number of adaxial hypodermal layers, seed shape, and the thickness of their seed coat. Phylogenetic trees based on multiple accessions also support the distinctiveness of M. sabuana and M. balbisiana var. andamanica from M. balbisiana var. balbisiana. Moreover, variation in the bract color of M. sabuana is confirmed by the current molecular study. Based on this integrated study, it is argued that M. sabuana and M. balbisiana var. andamanica are distinct and should be recognized taxonomically. Detailed morphological, anatomical and micro-morphological comparisons, color photographs, and a phylogenetic tree are provided.