Herbs annual, 8-15 cm tall. Stem branched from base; basal branches subopposite, spreading, densely papillate. Leaves alternate, crowded, narrowly lanceolate, compressed, densely papillate, margin membranous and usually reflexed near base, apex spinose mucronate. Flowers solitary, borne nearly throughout plant; bracts longer than bractlets, apex spinose mucronate; bractlets ovate, densely papillate, margin membranous at base. Perianth segments narrowly ovate, submembranous, hardened in fruit and appearing leathery, abaxially with a thickened process at middle, glabrous; portion of segment above process inflexed, with others forming a truncate surface tightly appressed to utricle, apex membranous, usually caducous and forming a circular hole. Anthers oblong, ca. 0.5 mm. Style very short; stigmas filiform. Seed horizontal, ca. 1.5 mm in diam. Fl. Jul-Aug, fr. Aug-Sep.
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