Calamus gibbsianus

Description

Calamus gibbsianus is a slender, clustering montane rattan that climbs to 8 m, rarely more, and is very rarely more or less stemless. The stem measures 4 - in diameter without sheaths, and 7 - with sheaths. The internodes are short, rarely exceeding 10 cm.

The sheaths are dull mid to dark green, sparsely to densely armed with pale green spines up to 7 mm long, occasionally also with minute spicules arranged in partial whorls. The sheaths and spines are all densely covered in brown indumentum. The knee is conspicuous, while the ocrea is inconspicuous to well developed, armed with groups of spicules or bristles. The flagellum reaches up to 1 m in length but is rarely absent.

The leaf is ecirrate, measuring up to 70 cm on climbing stems, longer in stemless forms. The petiole is 3 - long and sparsely to densely armed. The rachis is covered with rusty-brown hairs. The leaflets are regularly arranged, with 6–20 on each side of the rachis, distant to crowded and lanceolate in shape. Mid-leaf leaflets measure 45 - by 7 -. The leaflets are usually very densely covered with minute spine-like papillae or short bristles on the undersurface and occasionally on the upper surface, always with a dense tuft of orange to red-brown hairs on the undersurface at the leaflet base.

The inflorescence is usually about 1 m long, with 1–4 partial inflorescences up to 10 cm each. The inflorescence branches are strongly recurved and bear short recurved rachillae, large conspicuous saucer-like bracteoles, and relatively large flowers. The mature fruit is spherical to ovoid, measuring up to 16 mm by 12 mm, tipped by a short beak and covered in 15–18 vertical rows of pale brown, black-edged scales. The seed is ovoid to more or less oblong, up to 14 mm by 7 mm, deeply pitted and grooved, with subruminate endosperm. The seedling leaf is pinnate with about 6 leaflets.

Distribution and habitat

In Sarawak, Calamus gibbsianus is known only from one collection from the Kelabit Highlands. In Sabah, it occurs in montane forest on Mount Kinabalu and the Crocker Range at elevations of 1400 -. It grows primarily in the wet tropical biome.

Etymology

The species is named in honour of Lilian Suzette Gibbs (1870–1925), a British botanist and plant collector who made an important expedition to Mount Kinabalu.

Uses

In Sabah, Calamus gibbsianus has been used for general tying and weaving by successive expeditions to Mount Kinabalu.

Conservation

The species has been predicted to be threatened with extinction, although this assessment has low confidence.

References

References

1. [http://www.theplantlist.org/tpl1.1/record/kew-29535 The Plant List ''Calamus gibbsianus'']
2. Beccari, Odoardo. (1913). "Asiatic Palms - Lepidocaryeae". Annals of the Royal Botanic Garden, Calcutta.
3. Furtado, Caetano Xavier. (1935). "Palmae Malesicae". Gardens' Bulletin, Straits Settlements, Singapore.
4. Dransfield, John. (1992). "The Rattans of Sarawak". Forest Department Sarawak, Malaysia and Royal Botanic Gardens, Kew, UK.
5. "''Calamus gibbsianus'' Becc.". Royal Botanic Gardens, Kew.