1. Family: Arecaceae Bercht. & J.Presl
    1. Genus: Oncocalamus (G.Mann & H.Wendl.) H.Wendl.
      1. Oncocalamus macrospathus Burret

        This species is accepted, and its native range is W. Central Tropical Africa.

    [PW]
    General Description
    Clustered robust palm climbing to 20-35 m. Stems without sheaths, 18-30 mm in diameter, with 28-40 mm; internodes 18-24 cm long. Leaf sheaths very lightly striate, light moderately to profusely armed with upward-pointing brown spines; armature often concentrated on the sheath apex and often sloughing off at base leaving very feint circular scars; profuse white caducous indumentum present on mature and juvenile sheaths; ocrea ± horizontally truncate, somewhat striate, sometimes with a very slight (0.5-1 cm) rounded lobe abaxial to the leaf, armed as the sheath, although spines often concentrated at apex, extending up to 3 cm. Spear leaf dull yellow to bright green. Juvenile sheaths, armed as the mature sheaths only spines more profuse; leaves bifid, soon becoming pinnate; elaminate rachis up to 2 m long. Leaves on mature stems sessile, or with short (<2.5 cm long) petiole; rachis 1.5-2.0 m long, abaxially rounded, adaxially concave, becoming trapezoid then triangular in cross section distally, armed as the sheath, spines particularly profuse on underside, sparse on upper surface; cirrus up to 1.5 m long, ± triangular in cross section, unarmed; leaflets 30-40 on each side of the rachis, lightly pendulous, composed of a single-fold, linear-lanceolate, or ± sigmoid, boadly attenuate at the base, broadly to finely acuminate at apex, 35-45 cm long × 1.5-2.5 cm broad at the widest point, concolorous, armed along the margin with robust spines, particularly at base of leaflet, single-nerved, with 5-7 conspicuous secondary nerves on each side, lowermost leaflets smaller than the rest, somewhat erect or stiffly swept back across stem; acanthophylls up to 5 cm long. Inflorescences in successive, axils, ca.3m from stem apex; peduncle 15-20 cm long; peduncular bracts ca.3-4, 6-7 cm long; rachis up to 1.2 m in length, arching, pendulous; rachis bracts 2.5-4.5 cm long; rachillae, circular in cross-section, 25-35 cm long, pendulous, bracts bright yellow prior to anthesis, becoming dry, grey; prophyll subtending flower cluster 5-7 mm long, striate. Flower cluster with one central pistillate flower subtended by two lateral cincinni with one pistillate and 3-4 staminate flowers; staminate flowers 5 mm × 3.5 mm; calyx longer than the corolla, with short (<1 mm) stalk, tubular for the basal 2 mm; corolla, enclosed within the calyx, ca.4 mm long, tubular for the basal 1 mm; staminodial tube ca.2 mm long; anthers 0.8 mm × 0.2 mm; pistillode 2 mm × 0.5 mm; pistillate flowers similar to the staminate, 3.5-4.5 mm wide; ovary, 2.5 mm × 0.8 mm, tipped with a ca.1.5 mm long style. Fruit at maturity ± globose, 1.8-2 cm., with 18-20 vertical rows of scales. Seed sub-globose, 1.5-1.8 cm × 1.6-1.9 cm, smooth, lightly flattened to depressed below; sarcotesta <0.3 mm.
    Distribution
    Oncocalamus macrospathus is distributed from Cameroon, south of the Sanaga River, to Cabinda (Angola). This species is more commonly encountered in coastal forest although it also occurs in the lowland riverine forests of the Congo Basin.
    Biology
    This species is commonly found in forest margins, tree-fall gaps and other open areas and is particularly common in seasonally-inundated forest and alongside water courses.
    Conservation
    Least concern (LC).

    Images

    Distribution

    Native to:

    Cabinda, Cameroon, Congo, Equatorial Guinea, Gabon, Zaïre

    Oncocalamus macrospathus Burret appears in other Kew resources:

    Date Reference Identified As Barcode Type Status
    Dec 1, 2000 Louis [1350], Gabon K000520013
    Jun 15, 1999 Sunderland, T.C.H. [1913], Equatorial Guinea 64205.000
    Jun 15, 1999 Sunderland, T.C.H. [1913], Equatorial Guinea 64206.000
    Jun 15, 1999 Sunderland, T.C.H. [1913], Equatorial Guinea 64207.000
    Jun 15, 1999 Sunderland, T.C.H. [1913], Equatorial Guinea K000520018
    Jun 15, 1999 Sunderland, T.C.H. [1914], Equatorial Guinea K000520019
    Gossweiler [9092], Angola K000321011 isotype
    Gossweiler [9092], Angola K000321012 isotype
    Gossweiler [9092], Angola K000321013 isotype
    Gossweiler [9092], Angola K000321008 isotype
    Gossweiler [9092], Angola K000321009 isotype
    Gossweiler [9092], Angola K000321010 isotype
    Letouzey [11889], Cameroon K000520008
    Letouzey [11889], Cameroon K000520009
    Letouzey [11889], Cameroon K000520010
    Letouzey [11889], Cameroon K000520011
    Letouzey [11889], Cameroon K000520012
    Van Valkenburg [2628], Gabon K000208508

    First published in Notizbl. Bot. Gart. Berlin-Dahlem 15: 749 (1942)

    Accepted by

    • Sunderland, T.C.H. (2012). A taxonomic revision of the rattans of Africa (Arecaceae: Calamoideae) Phytotaxa 51: 1-76.
    • Figueiredo, E. & Smith, G.F. (2008). Plants of Angola Strelitzia 22: 1-279. National Botanical Institute, Pretoria.
    • Govaerts, R. & Dransfield, J. (2005). World Checklist of Palms: 1-223. The Board of Trustees of the Royal Botanic Gardens, Kew.

    Literature

    Palmweb - Palms of the World Online
    • T.C.H Sunderland, A taxonomic revision of the rattans of Africa (Arecaceae: Calamoideae) in Phytotaxa 51. 2012
    • Dowe, J.L., A taxonomic account of Livistona R.Br. (Arecaceae)
    Kew Backbone Distributions
    • Sunderland, T.C.H. (2012). A taxonomic revision of the rattans of Africa (Arecaceae: Calamoideae) Phytotaxa 51: 1-76.
    • Figueiredo, E. & Smith, G.F. (2008). Plants of Angola Strelitzia 22: 1-279. National Botanical Institute, Pretoria.

    Sources

    Herbarium Catalogue Specimens
    'The Herbarium Catalogue, Royal Botanic Gardens, Kew. Published on the Internet http://www.kew.org/herbcat [accessed on Day Month Year]'. Please enter the date on which you consulted the system.
    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 Selected Plant Families 2019. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

    Kew Names and Taxonomic Backbone
    The International Plant Names Index and World Checklist of Selected Plant Families 2019. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

    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