Calamus blumei
Clustering moderate rattan. Stem climbing to 20 m, without sheaths 0.8–1.2 cm diam., with sheaths to 2 cm diam., internodes to 25 cm. Leaf ecirrate; sheaths dull green but densely covered in greyish-yellow scales, drying grey, and scurfy caducous chocolate-coloured scales, and sparsely armed with short ± upward pointing spines to 3 mm, frequently borne on bulbous swellings; knee conspicuous; ocrea to 2 cm, dark brown; flagellum to 1.5 m; petiole to 15 cm; rachis to 45 cm long; leaflets to 6 on each side of the rachis, broad diamond-shaped, with short stalks and bristly wavy margins, to 20 x 7.5 cm, with 5–7 main nerves. Inflorescences to 1.25 m, the male and female superficially similar, the male branched to 3 orders, the female to 2 orders, with 3–4 partial inflorescences to 35 cm; male rachillae c. 20 x 1.5 mm, female to 70 x 3 mm. Mature fruit rounded to obovoid or ellipsoid, to 2.6 x 2.2 cm, covered in 18–20 vertical rows of yellowish to brownish scales. Seed to 2 x 1.3 cm; endosperm deeply ruminate. Seedling leaf with 2 diamond-shaped leaflets.
Never a common species, the main threats to this rattan are probably cane exploitation and forest clearance.
C. blumei is very easily identified with its diamond-shaped leaflets and ecirrate leaf; it is often confused with some species of Korthalsia but they are easily distinguished by the leaflets being diamond-shaped but not praemorse (with jagged edges) as in Korthalsia. Furthermore the presence of a flagellum will immediately indicate a species of Calamus. In Thailand it can only be confused with C. bousigonii. C. blumei occurs in a variety of forest types from sea level up to about 800 m elevation. It is shy to flower. The closely related C. tomentosus, occurring in Peninsular Malaysia, has been recorded for Thailand but we have seen no specimens. Hodel and Vatcharakorn mistakenly identified C. blumei as C. tomentosus and C. bousigonii as C. blumei.
Global — Peninsular Malaysia, Sumatra, Borneo (type).
Thailand — PENINSULAR: Chumphon, Surat Thani, Nakhon Si Thammarat, Trang.
Lowland and hill Dipterocarp forest.
A good quality cane.