Calamus diepenhorstii Miq.

Clustering rattan. Stems climbing to 20 m or more, without sheaths to c. 1.5 cm diam., with sheaths to 3 cm diam., internodes to c. 15 cm long. Leaves ecirrate; sheaths dull, often brownish-green, drying brown, armed with long black flattened spines to 4 cm long, usually less, sometimes with conspicuous swollen bases, brown scales abundant between the spines; knee conspicuous; ocrea poorly developed; flagellum to 2 m long; petiole 20–40 cm long; rachis curved, to 1m long; leaflets c. 15–30 on each side of the rachis, regularly arranged, curved, linear, the longest (in one form) to 35 x 1.4 cm, or (in another form) to 50 x 2 cm, bristly on main vein on upper surface, armed with 3 rows of bristles or densely covered with bristles on the lower surface. Inflorescence to 4 m, the male and female superficially similar, the male branched to 3 orders, the female to 2 orders, with c. 5 very distant, partial inflorescences, long pendulous; male rachillae c. 50 x 2 mm; female rachillae c. 70 x 3 mm. Mature fruit rounded, c. 2.2 cm diam., briefly beaked and covered in 16–21 vertical rows of brown scales. Seed rounded 1–1.2 cm diam., deeply pitted; endosperm ruminate. Seedling leaf bifid.