Bull. Natn. Sci. Mus., Tokyo, Ser. B, 31(2), pp. 63–65, June 22, 2005

Swertia japonica (Schult.) Makino var. latifolia Konta, a New Variety
from Hachijo Island, Tokyo, Japan
Fumihiro Konta
Department of Botany, National Science Museum,
Amakubo 4–1–1, Tsukuba, 305–0005 Japan
E-mail: konta@kahaku.go.jp

Abstract Swertia japonica (Schult.) Makino var. latifolia Konta is a new variety characterized bybroader leaves than those of typical variety of Swertia japonica (Schult.) Makino. This variety wasdiscovered in Mt. Mihara-yama in Hachijo Island, Tokyo, Japan. Several specimens cited in thispaper suggest that this variety is distributed in the Izu Islands as well as Honshu, mainland ofJapan.
Key words: new variety of Swertia japonica, var. latifolia, Hachijo Island, broad leaf.

Introduction

Description

A floristic investigation of vascular plants ofSuzaki, Shimoda City, in Izu Peninsula has been
conducted since 2000 as a project study of theNational Science Museum, Tokyo, under the titleof the Study on Environmental Changes in Sagami Sea and Adjacent Coastal Areas by Continuous Comparison of Fauna and Flora. Suzaki is asmall area located on the SE shore of the Izu
Peninsula and a very interesting place from theviewpoint of floristic study. Plentiful taxa of vascular plants distributed in seashore areas within
Japan are recognized in this area (Konta et al.,2005). Among these species, some are suspected
to have close relationship to their counterparts inthe Izu Islands where many endemic taxa are distributed (Ohba & Akiyama, 2002). I had achance to botanize in Hachijo Island for the comparison of floras between the Izu Islands and theSuzaki. A new variety of Swertia japonica(Schult.) Makino var. latifolia Konta, was foundin Hachijo Island, the southernmost one in theIzu Islands.

Swertia japonica (Schult.) Makino var. latifolia
Konta variety nov.
Affinis Swertiae japonicae var. japonicae, sedlamina valde lata diversus.
Habit. Stems erect, simple or branched fromthe base, up to 22 cm in height; cauline leaves atlower stems narrowly elliptic acute at base, obtuse at apex, (1.5)2–3.5 cm long, 3–5 mm wide,
those at higher stems narrowly elliptic with acuteapex, with strong bitter taste; flowers in dense
terminal panicles, 5-merous, calyx-segments linear to linear lanceolate, 9–12 mm long, corollalobes broadly lanceolate, 12–14 mm long, 4 mm
wide, white with purple nerves (Figs. 1–3).
Habitat. On muddy soil of cutting slope,sunny place, by a forest road in mountain area ofMt. Mihara-yama, ca. 570 m above the sea level(holotype).
Type. Japan. Honshu. Tokyo: Nishi-hakuunzan in Mt. Mihara-yama, Hachijo Machi, Isl.
Hachijo Island, F.Konta et al., 24080-a (Holotype; TNS, Fig. 1). F.Konta et al, 24080-b,24080-c (Isotype; TNS); Tokyo: Miyake Island,K.Hayashi, 10, Nov. 1935; Chiba: Kazusa Taitomisaki, S.Okuyama, 12, Nov. 1933; Shizuoka:
Mt. Ryusozan, Shizuoka City, H.Takahashi, 393;

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Fumihiro Konta

Fig. 1.

Holotype of Swertia japonica (Schult.) Makino var. latifolia Konta.

Swertia japonica (Schult.) Makino var. latifolia Konta, a New Variety

65

Kyoto: Ikagadani, Ohmiya Machi, Naka Gun,
N.Mariko, 14, Nov., 1991. (Paratypes; TNS).
Japanese name. Hiroha-senburi.
Notes. Swertia japonica (Schult.) Makino
var. latifolia Konta is similar in habit with thetypical variety, but differs from the latter in wider
leaves with 3 to 5 mm wide instead of needle
ones of the latter. Specimens cited above show
this new variety is not endemic in the Izu Islands.
References

Fig. 2. Leaves of Swertia japonica (Schult.)
Makino. A. var. japonica wth 1.5 mm wide, B.
var. latifolia with 5 mm wide.

Fig. 3.

Konta, F., S. Matsumoto & T. Katsuyama, 2005. New andinteresting taxa of vascular plants from Suzaki, Shimoda City, Central Japan. Bull. Natn. Sci. Mus., Tokyo,Ser. B, 31(1): 19–33.
Ohba, H. & S. Akiyama, 2002. A synopsis of the endemicspecies and infraspecific taxa of vascular plants of theIzu Islands. Mem. Natn. Sci. Mus., Tokyo, (38): 119–160.

Habit of of Swertia japonica (Schult.) Makino var. latifolia Konta in Hachijo Island.