Bull. Natl. Mus. Nat. Sci., Ser. B, 38(1), pp. 11–17, February 22, 2012 The Phylogeny of Japanese Enkianthus species (Ericaceae) Chie Tsutsumi* and Yumiko Hirayama Department of Botany, National Museum of Nature and Science, Amakubo 4–1–1, Tsukuba, Ibaraki 305–0005, Japan * E-mail:
[email protected] (Received 16 November 2011; accepted 28 December 2011) Abstract The genus Enkianthus consists of 12–17 species, most of which are distributed in China and Japan. We performed molecular phylogenetic analyses for Enkianthus species of Japan, using nuclear ITS, chloroplast matK with trnK intron, and trnS-trnG spacer regions. The result suggested that Enkianthus was separated into two groups; i.e., sect. Enkianthus with umbellate inflorescences and a clade of sect. Andromedina, sect. Enkiantella and sect. Meisteria with race- mose inflorescences. It also inferred that the ancestral Enkianthus seems likely to be shrubs with tubular or urceolate corollas and 4–5-apertured pollen, whereas the more derived species may pos- sess campanulate corollas and 3-apertured pollen. Kew words : Enkianthus, ITS, matK, molecular phylogeny, trnSG. Introduction ture, inflorescences structure, corolla shape, and morphologies of anther, pollen and seed (Ander- The genus Enkianthus Lour. (Ericaceae) is a berg, 1994; Kron et al., 2002). Infrageneric rela- genus of shrubs or small trees and often used as tionships of Enkianthus were studied by Ander- ornamental plants in the gardens. The genus con- berg (1994), who proposed a classification sists of 12–17 species (Anderberg, 1994; Kron et comprising four sections. Sect. Enkianthus has al., 2002; Fang and Stevens, 2005). All of the more or less coriaceous leaves, tubular or urceo- species are distributed from the Himalayas to late flowers, umbellate inflorescences, 4–5-aper- Japan (Fang and Stevens, 2005) and most of tured pollen, glabrous pedicels and smooth them are in China and Japan.