Hypodiscus synchroolepis Mast.

Plants in erect tussocks, 0.3-0.7 m high; rhizomes may be present. Culms simple, unbranched, smooth, 0.4-1.0 mm in diam. Leaf sheaths persistent, closely or loosely convolute. Male inflorescences with 2-10 bristly spikelets, compound; spathes persistent, as tall or taller than spikelets; bracts acuminate. Female inflorescences with 2-10 bristly spikelets, compound; spathes as long as or longer than spikelets, persistent, cartilaginous. Ovary unilocular with 2 white plumose styles fused at base to form a pillar. Flowering time Feb., Mar. Fruit an indehiscent nut, nut cap with several rows of ridges, wall smooth or tuberculate; elaiosome absent.