Calamus rudentum

Calamus (KAL-ah-muhs) rudentum (roo-DEHN-tuhm)
Nong Nooch Tropical Garden, Pattaya, Thailand. Photo by Paul Craft.
Scientific Classification
Genus: Calamus (KAL-ah-muhs) Species: rudentum (roo-DEHN-tuhm)
Synonyms
None set.
Native Continent
Asia
Morphology
Habit: Clustering Leaf type: Pinnate
Culture
Survivability index
Common names
wai boun, boun, (Lao Loum), wai pong (Thailand), probably also wai tabong, boun dam, boun khao (Lao Loum). Wai yae (หวายแย้), Wai pong (หวายโป่ง) (General); Wai khi sian (หวายขี้เสี้ยน) (Peninsular Thailand). Lizard Rattan (U.S.)

Habitat and Distribution

Thailand (all except North-east and West), Laos (Central and probably South) and Vietnam (Cochinchina).

Khao Yai National Park, Thailand. Photo by Dr. Scott Zona.

Probably also Cambodia (Gagnepain & Conrard 1937) and possibly also in northern Peninsular Thailand. In Laos recorded in scrub at 200 m, and probably also in lowland tropical moist forest. In Thailand in tropical moist forest at 100 - 400 m.

Description

The clustering stems of this climbing rattan palm from rainforests in Indo-China are only 2.5 cm (1 in.) thick without their sheaths but can reach astonishing length of 75 m (246 ft.) It is best suited to the tropics and will doubtlessly require some tall trees for support. (RPS.com)

Very robust clustering rattan. Stem climbing to 75 m, usually less, without sheaths 2.5–3.5 cm in diam., with sheaths 4–7 cm diam.; internodes to 30 cm or more long. Leaf ecirrate; sheaths tending to split deeply opposite the petiole, light to yellowish green, very densely armed with a wide range of different sized spines, including large reflexed flattened red-brown spines to 5 cm long borne in oblique partial whorls, particularly below the petiole, and much smaller black needle-like spines to 5 mm long, also borne in short partial whorls, and scattered ungrouped spines, and particularly large erect pale brown flattened spines to 15 cm long, borne around the leaf sheath mouth; knee inconspicuous, not greatly swollen and almost entirely obscured by the sheath spines; ocrea inconspicuous; flagellum massive to 6 m or more long; petiole 20–60 cm long, densely armed with partial whorls of spines as on the leaf sheath; rachis to 3.5 m long, bearing regularly arranged, close, linear-lanceolate leaflets, the largest to 45–65 x 1.5–2.5 cm, with robust bristles at least 10 mm long on the adaxial and abaxial surfaces of the main vein, the margins also bristly. Inflorescences male and female superficially similar, the male branching to 3 orders, the female to 2 orders, to 6.5 m long including the long terminal flagellum with up to 8 or more well spaced pendulous partial inflorescences, each up to 1.5 m long; male rachillae to 20 x 0.2–0.3 cm; female rachillae 12–35 x 0.3–0.4 cm. Mature fruit ovoid, about 1.8 x 1.2 cm, covered in 13 vertical rows of yellowish brown deeply channelled scales with thin dark margins. Seed globose about 0.9 cm in diam.; endosperm homogeneous. Seedling leaf with 4–6 linear leaflets. (J. Dransfield, A Synopsis of the Rattans (Arecaceae: Calamoideae) of Laos and Neighbouring Parts of Indochina. 2002)/Palmweb. Editing by edric.

Comments and Curiosities

Uses: The cane is of high quality and suitable for trade. The shoot is edible and the fruits are sometime sold as food. There are reportedly plantations for cane production in Vietnam.

Conservation: Unknown. Reportedly a preferred species for trade in Vietnam, so harvesting pressures may be high.