Calamus trachycoleus Becc., Ann. Roy. Bot. Gard. (Calcutta) 11(App.): 108 (1913)

Primary tabs

https://media.e-taxonomy.eu/palmae/photos/palm_tc_29985_4.jpg

Distribution

Map uses TDWG level 3 distributions (https://github.com/tdwg/wgsrpd)
Borneo present (World Checklist of Arecaceae)B
Restricted to the floodplains of large rivers in south, central and east Kalimantan, where it has been cultivated for over a hundred years. (Dransfield, J. & Patel, M. 2005: Rattans of Borneo, an interactive key.)A

Conservation

  • Least concern. (Dransfield, J. & Patel, M. 2005: Rattans of Borneo, an interactive key.)A

Description

  • Habit - Climbing; stems clustering; not branching in the forest canopy; not dying after flowering. Plants dioecious.
    Leaf-sheath - Tubular for most of its length; stem and sheath together 1.35-1.65 cm; flagellum absent; knee present; with fewer spines than the rest of the sheath. Sheath surface lacking small horizontal ridges; without hairs or minute spines; green; scales on surface lacking. Leaf sheath with abundant spines; spines persistent; horizontally pointing; of different sizes; the larger spines tapered; the longest, excluding those at the mouth of the sheath 1-3cm. Spines straight; in life same colour as the leaf sheath; with smooth margins; the bases downswept and crescent-like. Spines mostly not grouped. Spines around the leaf sheath mouth scarcely different from those on the rest of the sheath. Ocrea - Absent. Leaf-stalk - Absent or usually less than 3cm. Leaves - Cirrate; rachis armed; not hairy. Undersurface of newly emerged leaflets same as upper surface. Scales absent from leaflet surfaces. Leaflets sessile; 11 to 39 on each side of rachis; irregularly spaced and parallel; held in a single plane; lanceolate, or linear-lanceolate; the leaflet tip acute, or cucullate (hooded). Longest leaflet 27.9-34.1 cm; 2 to 5cm wide; with none or very few bristles; the margins with many bristles. Bristles not interlocking; stiff black greater than 0.5mm long. Leaflets scarcely plicate; the veins not radiating; midrib not raised and prominent. Lowermost leaflets reflexed across the stem. Apical leaflets not or scarcely joined; not less than 4 cm long.
    Inflorescence - Inflorescence axis erect along the axis, with clawed spines on the primary bracts; not rooting at its tip; about the same length as the leaves; the first bract not enclosing the inflorescences at anthesis. Partial inflorescence present; bracts at the base of the partial inflorescences wholly tubular with a neat mouth or a small open limb, much shorter than the partial inflorescence. Rachilla lacking an enclosing bract; not at all pressed against the subtending bract. Flowers arranged in two rows. Male rachillae not less than 1 cm long. Female rachillae not congested; without conspicuously stalked flower cups. Bracts on the rachillae not net-like.
    Fruit - At maturity 1.1-1.3 cm; ellipsoid; red resin (Dragon's blood) absent; one seeded. Fruit scales with a conspicuous central groove; the tips not recurved; colour on ripe fruit greenish-white; when dry straw-brown or yellow-brown (excluding dark margins). Seed cylindrical; the surface superficially or finely pitted; endosperm ruminate. (Dransfield, J. & Patel, M. 2005: Rattans of Borneo, an interactive key.)A

Notes

  • Similar to Calamus caesius but differing in the stoloniferous habit and the very fine short spines mixed with larger spines on the leaf sheaths. Now introduced in to Sabah and Sarawak. (Dransfield, J. & Patel, M. 2005: Rattans of Borneo, an interactive key.)A

Bibliography

    A. Dransfield, J. & Patel, M. 2005: Rattans of Borneo, an interactive key.
    B. World Checklist of Arecaceae