Volume 11 > Part 3 > Year 2013 > Page 414 > Arecaceae > Eugeissona

Eugeissona tristis Griff.wfo-0000956214

Calcutta J. Nat. Hist. 5: 101. 1845. Plate CIV: A & B.

Accepted Name : This is currently accepted.

Description : Fiercely spiny acaulescent palm forming dense thickets of up to 12 individual stems in the forest undergrowth. Leaves 7–10 per mature shoot, up to 8 m long; petiole up to 3 m long, up to 5 cm diam. at the tip of the ligule, densely covered with irregularly arranged shiny black spines to 5 cm long, decreasing in size towards the petiole tip; rachis armed as the petiole; leaflets to 100 or more on each side of the rachis, regularly arranged, with abundant black bristles along the midrib, the longest leaflets to 90 by 2–4 cm. Inflorescence system terminal, shorter than the leaves, to 5 m tall, subtending leaves of lateral inflorescences gradually decreasing to bracts; ultimate branches terminating in cupules of 12–13 tightly imbricate brown striate unarmed bracts, enclosing a pair of flowers comprising a male and a hermaphrodite flower, the males of the inflorescence emerging first, followed by the hermaphrodite flower. Male flowers borne on a short pedicel, to 1 cm long, to 6 cm long, shiny brown; calyx to 2 cm, striate; petals to 6 cm, tubular at the base, distally split into 3 spine-tipped woody petals; stamens 22–27, anthers elongate, dangling at anthesis. Hermaphrodite flower similar to the male flower, but with an asymmetrically flattened tip in bud; gynoecium ovoid, tipped with conspicuous pyramidal stigma. Fruit at maturity 7–9 by 3–5 cm, beaked; epicarp scales brown, somewhat irregularly arranged; endocarp with 3 + 3 flanges penetrating the homogeneous endosperm.

Thailand : PENINSULAR: Yala, Narathiwat.

Distribution : Peninsular Malaysia (type).

Ecology : Hill slopes and ridge tops in hill dipterocarp forests, to 1,000 m alt.

Vernacular : Chak khao (จากเขา)(Narathiwat); chak cham (จากจํา)(Yala, Pattani); sue-dae (ซือแด)(Malay-Narathiwat).

Uses: Edible young endosperm; leaves used for short-lived thatch.

Conservation Status: Not threatened.

Notes: This species is very abundant in Peninsular Malaysia, but occurs only in the extreme south of Thailand. It is considered a serious pest of hill forest. When the forest canopy is opened during selective logging of timber trees, any Eugeissona tristis present then increases dramatically and prevents regeneration of timber trees.