The Symplocaceae of Japan

Abstract

A taxonomic revision of the family Symplocaceae (Symplocos Jacq. only) in Japan is provided. Throughout a broad survey of herbarium specimens and living plants in the field, pollen grains, inflorescences, and fruits are found to be major source of taxonom-ic character. Twenty-three species are recognized in Japan, one species (S. sonoharae) being assigned to subgen. Symplocos, and 22 species to subgen. Hopea (L.) Clarke. The species of subgen. Hopea are further classified into eight sections. Keys, distribution maps and complete synonymy with full description for all species are provided. Six new taxa are described and two new names are proposed : sect. Glaucae, sect. nov.; sect. Lancifoliae, sect. nov.; sect. Okinawenses, sect. nov.; S. sonoharae var. oblonga, var. nov. (from China); S. liukiuensis var. iriomotensis, var. nov.; S. prunifolia var. tawadae, var. nov.; S. kuroki, nom. nov.; S. sawafutagi, nom. et stat. nov. The first chromosome counts of three Japanese species are also presented : 2n = ca. 90 in S. sonoharae; n = 11 in S. stellaris; 2n = 22 in S. tanakae.