Generic classification of Amaryllidaceae tribe Hippeastreae
by Nicolas Garcia, Alan W. Meerow, Silvia Arroyo-Leuenberger, Renata S. Oliveira, Julie H. Dutilh, Pamela S. Soltis, Walter S. Judd
A robust generic classification for Amaryllidaceae has remained elusive mainly due to the lack of unequivocal diagnostic characters, a consequence of highly canalized variation and a deeply reticulated evolutionary history. A consensus classification is proposed here, based on recent molecular phylogenetic studies, morphological and cytogenetic variation, and accounting for secondary criteria of classification, such as nomenclatural stability. Using the latest sutribal classification of Hippeastreae (Hippeastrineae and Traubiineae) as a foundation, we propose the recognition of six genera, namely Caligolirion gen. nov., Hippeastrum, Phycella s.l., Rhodolirium s.s., Traubia, and Zephyranthes s.l. A subgeneric classification is suggested for Hippeastrum and Zephyranthes to denote putative subclades. In Hippeastrum, we recognize H. subg. Hippeastrum and H. subg. Tocantinia. In Zephyranthes, Z. subg. Eithea, Z. subg. Habranthus, Z. subg. Myostemma (= core Rhodophiala clade), Z. subg. Neorhodophiala subg. nov., and Z. subg. Zephyranthes are recognized. Descriptions, synonymy, taxonomic keys, and new combinations are provided for each genus and subgenus.