Howea Becc.
  • Malesia 1: 41 (1877) 


Notes: Distribution: Lord Howe I.

General Description

Moderate, solitary, unarmed, pleonanthic, monoecious palms. Stem erect, bare, conspicuously marked with close, horizontal or oblique leaf scars, the base sometimes expanded into a knob. Leaves pinnate, neatly abscising but not forming a crownshaft; sheath well developed, splitting longitudinally opposite the petiole, disintegrating into an interwoven mass of fine fibres; petiole short to moderately long, flattened or slightly channelled adaxially, abaxially ± angled, sparsely to densely scaly; rachis ± rounded to angled abaxially, adaxially angled, scaly as the petiole; leaflets numerous, single-fold, regularly arranged, curved or stiffly ascending, acute, acuminate or minutely bifid, adaxially with sparse scattered scales, abaxially ± glabrous or rather densely dotted with scales and bearing abundant floccose indumentum and ramenta along the midrib, transverse veinlets obscure. Inflorescences interfoliar, sometimes becoming infrafoliar after leaf fall, short or almost as long as the leaves, spicate, solitary or compound with up to 3–8 borne together on a common axillary boss, erect at first, later pendulous, protandrous; peduncle ± elliptic in cross-section, much shorter than or ± equalling the rachis, densely scaly; prophyll tubular, membranous; peduncular bract inserted near to or some distance from the prophyll, enclosing the inflorescence until anthesis, ± membranous, tubular, later splitting down its length, disintegrating and falling, leaving a low collar; rachis robust, scaly, densely covered with spirally arranged, ± spreading, low, rounded or triangular, rigid, coriaceous bracts, each forming a lip to a floral pit, enclosing a triad of flowers, except at the very tips where pits enclosing paired staminate flowers; floral bracteoles ± sepal-like. Staminate flowers partially exserted one at a time from the pit at anthesis; sepals 3, distinct, imbricate, usually keeled, ± rounded, the margins toothed; corolla with a stalk-like base ± as long as the sepals, and 3 ovate, valvate lobes; stamens 30–70 or more, filaments elongate, variously connate at the base for much of their length, the connective sometimes prolonged into a point, anthers elongate, ± latrorse; pistillode absent. Pollen ellipsoidal, asymmetric to pyriform; aperture a distal sulcus; ectexine tectate, finely perforate-rugulate, or granular-rugulate, especially on proximal face, aperture margin finely perforate-rugulate; infratectum columellate; longest axis 37–52 µm [2/2]. Pistillate flowers ± globular; sepals 3, distinct, imbricate, rounded, the margins toothed; petals 3, distinct, basally strongly imbricate, the tips briefly valvate; staminodes 3–6, forming a low, irregularly lobed, membranous ring, or irregularly separated as triangular or bifid flanges; gynoecium unilocular, uniovulate, tipped with 3 short stigmas ± reflexed at anthesis, ovule laterally attached, campylotropous. Fruit ovoid, sometimes faintly ridged, 1-seeded, shiny dark green at first, turning dull yellowish-green or reddish-brown, perianth whorls persistent, stigmatic remains apical; epicarp smooth, mesocarp rather thinly fleshy with abundant longitudinal fibres, endocarp cartilaginous, not adhering to the seed. Seed laterally attached, raphe extending 1/3 the length of the seed or less, endosperm homogeneous; embryo basal. Germination adjacent-ligular; eophyll bifid. Cytology: 2n = 32.

Diagnostic Description

Spectacular pinnate-leaved palms endemic to Lord Howe Island, where they occur in huge populations; distinctive in the robust pendulous spicate inflorescences and staminate flowers with large numbers of stamens.

Morphology

Leaf (Tomlinson 1961), root (Seubert 1998a,1998b), and fruit (Essig 2002).

Biology

Howea forsteriana is abundant on the island in lowland forest on sandy areas; H. belmoreana can be found as scattered individuals with H. forsteriana, but becomes abundant at higher elevations up to about 450 m above sea level. Wind has been shown to be the primary pollinator, one of the few proven examples in the palms (Savolainen et al. 2006).

Distribution

Two easily distinguished species endemic to Lord Howe Island.

Uses

Both species, but especially Howea forsteriana, are important as commercially grown ornamentals.

Common Names

Kentia palms, Howea palms, sentry palms.

Distribution Map

 
  • Native distribution
  • Introduced distribution
Found in
  • Australasia Australia Norfolk Is.
Introduced into
  • Southern America Caribbean Dominican Republic

  Bibliography

  • 1 J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008
  • 2 Govaerts, R. & Dransfield, J. (2005). World Checklist of Palms: 1-223. The Board of Trustees of the Royal Botanic Gardens, Kew.

 Information From

Palmweb - Palms of the World Online
http://www.palmweb.org
Palmweb 2011. Palmweb: Palms of the World Online. Published on the internet http://www.palmweb.org. Accessed on 21/04/2013
  • A Content licensed under Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License
  • B http://creativecommons.org/publicdomain/zero/1.0
eMonocot
http://e-monocot.org
eMonocot. (2010, 1st November). Retrieved Wednesday, 8th February, 2012, from http://e-monocot.org.
  • C Content licensed under Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License
World Checklist of Selected Plant Families
http://apps.kew.org/wcsp/
WCSP 2014. 'World Checklist of Selected Plant Families. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet; http://apps.kew.org/wcsp/ Retrieved 2011 onwards
  • D See http://kew.org/about-kew/website-information/legal-notices/index.htm You may use data on these Terms and Conditions and on further condition that: The data is not used for commercial purposes; You may copy and retain data solely for scholarly, educational or research purposes; You may not publish our data, except for small extracts provided for illustrative purposes and duly acknowledged; You acknowledge the source of the data by the words "With the permission of the Trustees of the Royal Botanic Gardens, Kew" in a position which is reasonably prominent in view of your use of the data; Any other use of data or any other content from this website may only be made with our prior written agreement.