A Classification of the Genus Rhododendron sect. Brachycalyx (Ericaceae) in Japan (2)

Abstract

Keys to species and infraspecific taxa of Rhododendron subg. Tsutsusi sect. Brachycalyx in Japan based on flowering and fruiting plants are presented. Species and infraspecific taxa recognized in this study with information on their synonymy, distinctions and ecological/distributional remarks are emumerated in each series. Rhododendron osuzuyamense T. Yamaz. which had not been validly described, is validated. Six new nomenclatural novelties, viz. R. weyrichii var. purpuriflorum (T. Yamaz.) Minamitani, R. dilatatum f. decandrum (Makino) Minamitani, f. inobeanum (Honda) Minamitani and f. pilosum (H. Hara) Minamitani, R. lagopus f. niphophilum (T. Yamaz.) Minamitani, and R. kyushuense f. glabrescens (Nakai ex H. Hara) Minamitani, are proposed. Six new forms, viz. R. tashiroi f. album Hatus. ex Minamitani, R. osuzuyamense f. albiflorum Hatus. ex Minamitani, R. hyugaense f. albiflorum Hatus. ex Minamitani, R. nudipes f. lobatum Minamitani and f. fugenense Minamitani, and R. kiyosumense f. glabrescens Minamitani are described. The lectotype of R. wadanum Makino is designated. (Continued from J. Jpn. Bot. 93(2): 75–103, 2018)