两广石山棕 liang guang shi shan zong

Rhapis grossifibrosa Gagnepain, Notul. Syst. (Paris) 6: 159. 1937; R. filiformis Burret.

Stems solitary or clustered, to 2.5 m tall, 2-8 cm in diam., erect or leaning, densely covered with persistent leaf bases. Leaf sheath fibers stout, black or dark brown, curved, remaining joined, not separating into stiff spines, forming a distinct point opposite petiole; petioles 0.4-1 m, smooth along margins; blades 35-85 cm wide, sometimes undivided, usually divided into 2-21 segments, these to 45 × 1.5-6 cm, scarcely silvery white abaxially. Inflorescences interfoliar, to 0.8 m, with 2-5 partial inflorescences; rachillae many, to 10 cm; flowers unisexual; male flowers to 2.5 mm, with 6 stamens; female flowers to 2.2 mm. Fruits blue-black, ellipsoid to ovoid, to 1 × 1 cm.

Seasonal forests on steep slopes of karst limestone hills; 500-1100 m. Guangdong, Guangxi [Vietnam].