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)

Following nomenclatural novelties are proposed for the Japanese subtribe Arundinariinae of Poaceae subfam. Bambusoideae tribe Arundinarieae. 1) An intergeneric hybrid, ×Pleiopseudosasa simojaponica, 2) two new combinations, –Neosasamorpha akiuensis and Sasaella yamakitensis, are published. 3) 19 varieties are merged into their typical species. 4) Three clonal complexes of hybrid origin are described in the genus Sasa.

A new variety of Halenia (Gentianaceae), H. corniculata (L.) Cornaz var. dissimilis K. Ueno & Y. Ueno, is described from Ooshika village, Nagano Prefecture, central Japan. It is similar to H. corniculata var. corniculata, but lacks corolla spurs completely which characterizes Halenia from other genera among Gentianaceae.

Monolophus coenobialis Hance (Zingiberaceae), a yellow-flowered species, is recorded for the first time from India. The species was earlier recorded only from Guangdong and Guangxi in south China. Details described and illustrated based on morphological characteristics observed in the field are provided.