Russia Flora: Tree up to 12 (in Japan up to 20) m tall. Terminal buds dark brown, about 5 mm long, finely hairy. Shoots brown or yellow-brown, more or less densely pubescent at nodes. Leaves 5-7-lobed, 5-11 cm long, 7-15 cm wide, cordate at base, rather thin, glabrous above, with tufts of short hairs in vein angles below, sometimes hairy along all veins; leaf lobes broadly triangular, abruptly narrowed into short pointed tip, entire-margined, length not exceeding 1/2 of leaf length. Petioles 5-10 cm long, thin, more or less densely pubescent. Inflorescence many-flowered, glabrous. Flowers about 8 mm in diameter, petals yellow or greenish-yellow, narrowly oblong-oval, glabrous; sepals ovate, obtuse, glabrous or slightly hairy at base; stamens 8, longer than petals, glabrous. Samaras 2.5-3.5 cm long, diverging at acute angle. (Table XIX).

Distribution: North Sakhalin, South Sakhalin, South Kuril (Fig. 63). - In deciduous and mixed forests, also along edges of coniferous forests, along stream banks, seashores and terraces. Flowering in May. Ornamental, with useful properties similar to A. mono.

General distribution: Japanese-Chinese (islands of Hokkaido and Honshu). - Described from Japan.

Note: The name A. pictum Thunb. (1784. Fl. Jap.: 162) has priority over A. mayrii and A. mono. However, the type specimen of A. pictum, as established by Nakai (1935), belongs to a species of the genus Kalopanax Miq. (Araliaceae). A. I. Poyarkova in "Flora of the USSR" applied the name A. pictum to the Sakhalin-Japanese maple following established tradition; but according to modern nomenclatural rules (International Code of Botanical Nomenclature, 1980, Art. 62.1), such a decision is no longer acceptable.