Mitella japonica Maxim

M. Wakabayashi, 2006, Tiarella and Mitella, Flora of Japan, Volume 2 b: Angiospermae-Dicotyledoneae: Archichlamydeae (b), Kodansha, pp. 70-75 : 74-75

10. Mitella japonica Maxim ,

in Bull. Acad. Imp. Sci. St.-Petersbourg 11: 431 (1867), pro parte.

Mitella japonica Miq ., Ann. Mus. Bot. Lugd.-Bat. 3: 96 (1867), as '(Siebold et Zucc.) Miq.'

Mitella longiscapa Makino in Bot. Mag. Tokyo 8: 43 (1894), quoad syn. Maxim.

[ Mitellopsis japonica Siebold et Zucc. in Abh. Math.-Phys. Cl. Kdnigl. Bayer. Akad. Wiss. 4: 190 (1845), nom. nud.]

[ Mitella triloba Miq ., Prolus. FI. Jap.: 378 (1867), nom. nud.]

Japanese name: O-charumeru-so.

Perennial herbs. Rhizomes thickened, hypogaeous, with a tuft of leaves at apex. Radical leaf blade narrowly ovate or narrowly triangular, cordate, acute to short acuminate, 4-10 cm long, 2-6 cm wide, usually shallowly 5-lobed, irregularly incised and acutely toothed, upper surface long hirsute, green, lower surface hirsute and glandular pubescent on nerves, pale green, often with purplish tinge; petiole 3-15 cm long, densely short glandular hairy, often with long glandular hairs, with a pair of axillary stipules at base; stipules scarious, densely long hairy along margin. Flowering stems 20-40 cm tall, erect, densely glandular pubescent. Inflorescences racemes, many-flowered. Flowers April to May; pedicel ca. 2-3 mm long, minutely glandular. Calyx tube obconical, densely glandular pubescent, greenish; calyx lobes 5, triangular or depressed-triangular, acute, glabrous adaxially, sparsely glandular abaxially, ca. 0.9 mm long, spreading or often reflexed, greenish. Petals 5, 3-7-pinnatiparted, glandular dotted, 2.5-3 mm long, spreading or slightly reflexed, greenish; pinnae slender, spreading or slightly obliquely ascending. Stamens 5, alternate calyx lobes, adjacent to base of petals, ca. 0.8-1.1 mm long; anthers ovoid, cordate, 0.7-0.9 mm long at anthesis, yellow. Disc prominent, flat, greenish. Ovary inferior. Styles 2, erect, ca. 0.5 mm long; stigmas thickened, shallowly 2-5-lobed, yellowish green. Seeds oblong, ca. 1.1 mm long, scabrous, with narrow longitudinal areolae elevated slightly, without papillae, brownish.

Chromosome number: 2n = 28 (Wakabayashi 1973).

Japan: Honshu (S. Kinki Dist.), Shikoku and Kyushu. Moist, shady places along streams in mountainous areas. Endemic.

Icones: Kitamura & Murata, Herb. PI. 2: t. 35 300; Terasaki, rev. ed.: f. 1158; Satake et al., Herb. PI. 2: photo. 154 1 & 2.