Acanthophoenix rousselii N.Ludw.

First published in Palms (1999+) 50: 84 (2006)
This species is accepted
The native range of this species is S. Central Réunion. It is a tree and grows primarily in the wet tropical biome.

Descriptions

Biology
See protologue pdf.
Distribution
This species has a limited distribution within the town limits of Le Tampon. It grows in Trois Mares at an altitude of 600–850 m, in remnants of a transitional lowland forest ecosystem specific to the leeward side of the island.
General Description
Solitary pleonanthic monoecious palm with erect trunk to 15–25 m tall and 20–30 cm diam., surface light gray, rather smooth, only slightly marked with leaf scars; trunk base swollen in a characteristic “elephant foot.” Leaves pinnate, 15–20 in crown; crownshaft conspicuous, , sheaths 90–120 cm long, 45 cm wide at the base, up to 6 mm thick, abaxially dark brown, covered with dense furlike black hair 6–8 mm long, except on half length median axis where glabrous; petiole and rachis 2.50–3 m long, glabrous or with a fine indument abaxially in the distal part; leaflets 70–80 pairs, pendulous and regularly attached on both edges of the rachis, leaflet tip acute, olive green color on both surface, leaflet midrib adaxially armed with thin reddishbrown bristles 2–4 cm long, thin flexuous dotlike scales on abaxial side of midrib. Inflorescences infrafoliar, first enclosed in a tough unarmed brown prophyll; inflorescences ivory-colored, pendulous, 100–110 cm long, branching to 2 orders with 50–70 rachillae; peduncle base enlarged in a crescent shape where attached to the trunk; peduncle and rachis armed with strong sinuous black spines 2–3 cm long; rachillae bearing densely arranged triads of flowers, two staminate flowers flanking one pistillate flower, all sessile and glabrous. Staminate flowers 12 × 12 mm, ivory white turning to light yellow except pistillode and basal part of filaments pinkcolored; sepals 3, narrow triangular with acute tip, 1.5 mm long; petals 3, elliptic, valvate, 7 × 3 mm; stamens 9 (sometimes 8) with white sagittate anthers 3–4 mm long and coiled filaments 8 mm long; pistillode 2–3 mm with trifid tip. Pistillate flowers ivory-white, globose to subspherical, slightly asymetrical, smaller than staminate flowers 4.5 × 3–4 mm; sepals and petals similar, membranous, imbricate. Mature fruit black with persistent beige or light brown perianth, ellipsoidal and slightly curved, 15–20 × 8 mm; mesocarp thin, dark purple; endosperm homogenous, embryo basal.
Diagnostic
a A. rubra staminibus plerumque 9 vice 11 vel plus, fructu curvato vice ellipsoideo differt, a A. crinita staminibus 9 vice 6, fructu multo majore et eophyllo pinnato vice bifido differt.
Conservation
See protologue pdf.
[PW]

Uses

Use
See protologue pdf.
[PW]

Sources

  • Herbarium Catalogue Specimens

    • Digital Image © Board of Trustees, RBG Kew http://creativecommons.org/licenses/by/3.0/
  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2022. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2022 World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0
  • Kew Names and Taxonomic Backbone

    • The International Plant Names Index and World Checklist of Vascular Plants 2022. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2022 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0
  • Kew Science Photographs

    • Copyright applied to individual images
  • Palmweb - Palms of the World Online

    • Palmweb 2011. Palmweb: Palms of the World Online. Published on the internet http://www.palmweb.org. Accessed on 21/04/2013
    • Content licensed under Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License http://creativecommons.org/licenses/by-nc-sa/3.0