Korthalsia rigida

Korthalsia (kohr-tahl-SEE-ah) rigida (rih-GEE-dah)
Singapore. Photo by Wee Foong Ang.
Scientific Classification
Genus: Korthalsia (kohr-tahl-SEE-ah) Species: rigida (rih-GEE-dah)
Synonyms
None set.
Native Continent
Asia
Morphology
Habit: Clustering Leaf type: Pinnate
Culture
Survivability index
Common names
Wi Dahan (Ib.)

Habitat and Distribution

Borneo, Malaya, Philippines, Sumatera, and Thailand. Widespread throughout Brunei at

Singapore. Photo by Wee Foong Ang.

altitudes up to about 500 m above sea level. Elsewhere throughout Borneo, Palawan, Sumatra, Malay Peninsula, and south Thailand. K. rigida is found in lowland and hill dipterocarp forests at altitudes up to 900 m but appears to avoid peat swamp forest.

Description

Moderate rattan, clustering, frequently branching in the canopy, climbing to 50 m or more. Stem without sheaths to 2 cm in diam., usually less, with sheaths to 2.5 cm, internodes to 20 cm or more. Sheaths dull green, densely covered with persistent grey indumentum and deciduous chocolate-coloured scales, and sparsely armed with triangular spines to 10 mm, rarely densely armed (juvenile shoots); ocrea to about 4 cm long, tightly sheathing, ± truncate with a narrow tattering margin, rarely splitting, usually unarmed. Leaf to about 1.5 m long, including the petiole to 10 cm and cirrus to 75 cm. Leaflets about 5-7 on each side of the rachis, shining dark green on upper surface, bluish-grey beneath, the longest to 15 × 8 cm, borne on a short stalk to 2.5 cm, chocolate coloured scales occasionally present on ribs on the undersurface. Inflorescences produced from topmost up to 12 nodes, highly branched to 80 cm, bearing about 8 partial inflorescences on each side, each with about 10 rachillae; rachillae slender, inconspicuously tomentose, to 150 × 5 cm, dull dark brown. Fruit rounded, about 1 cm in diam., with 15 vertical rows of dark green to dull brown scales. Seed about 8 mm in diam., irregularly ruminate. Seedling leaf simple, dark shiny green on upper surface, grey beneath. (J. Dransfield, The Rattans of Brunei Darussalam. 1997)/Palmweb. Editing by edric.

It may be confused with the closely related K. paucijuga, not yet recorded for Brunei, but the latter is much more slender, has no petiole, only 3-4 leaflets on each side of the rachis and a very small inflorescence with inflated primary bracts. (J. Dransfield, The Rattans of Brunei Darussalam. 1997)/Palmweb.

Culture

Cold Hardiness Zone: 10b

Comments and Curiosities

Etymology: Specific epithet from the latin rigida, literally; Rigid.

Uses: Mainly local use.