心叶组 xin ye zu

Roots smooth. Stem evenly swollen, cylindric, leafy, usually tall, in some species deciduous. Leaves closely spaced, distichous, in 2 rows, usually short, stiffly textured, base cordate, clasping, and decurrent into sheaths. Inflorescences borne at each node on recent and older leafy stems, 1- to several flowered. Flowers solitary, leaf opposed, resupinate or not resupinate, usually white, medium-sized, shortly pedicellate. Sepals and petals sometimes reflexed; mentum straight, narrowly saccate, its elements fused distally into a spur.

About 30 species: Himalayas to Oceania, most in Indonesia; one species in China.