Herbs , perennial, with nonstinging hairs. Stems 1-25-branched, repent, filiform, mat-forming. Leaves alternate; stipules absent. Leaf blades orbiculate to oblong, margins entire; cystoliths elongate, linear. Inflorescences axillary, 1-flowered. Flowers unisexual, proximal flowers pistillate, the distal staminate; bracts subtending pistillate flowers developing 3 corky wings covered with fine, hooked hairs in fruit. Staminate flowers: tepals 4, distinct, equal; stamens4; pistillode obovate. Pistillate flowers: tepals 4, connate, lacking hooked hairs; staminodes absent; stigma filiform, deciduous. Achenes sessile, ovoid, apex acute, tightly enclosed by scarious perianth and surrounded by connivent, winged bracteoles. x =10. This monotypic genus was first reported naturalized in California in 1940.