1. Petrosimonia sibirica (Pallas) Bunge, Mém. Acad. Imp. Sci. Saint Pétersbourg, sér. 7. 4(11): 60. 1862.
叉毛蓬 cha mao peng
Polycnemum sibiricum Pallas, Ill. Pl. 61. 1803; Halimocnemis sibirica (Pallas) C. A. Meyer.
Plants 15-40 cm tall, densely pilose. Stem simple or branched from base, erect or decumbent; branches all opposite, obliquely spreading. Leaves all opposite, linear, usually appearing slightly sickle-shaped, semiterete, 1-3.5 cm × 1-1.5 mm, adaxially plane or sulcate, base slightly expanded, expanded part usually becoming leathery in fruit, apex acuminate. Bractlets navicular, margin membranous, apex subulate, recurved. Perianth segments 5, membranous, outer 3 elliptic-ovate, inner 2 lanceolate, slightly shorter than or equaling bractlets, proximally thickened and becoming leathery in fruit, abaxially villous near apex, apex acuminate. Stamens 5; filaments exserted from perianth, compressed, ca. 2 × as long as perianth; anthers purple-red or orange-red, ca. 2.5 mm; appendage apex 2-toothed. Stigmas equaling style. Utricle light yellow, broadly ovate; pericarp distally slightly fleshy. Seed vertical, subglobose, compressed, ca. 1.5 mm in diam. Fl. and fr. Jul-Sep.
Gobi desert, saline-alkaline deserts, arid slopes. N Xinjiang [Russia (S Siberia); C Asia].