Latania Comm. ex Juss., Gen. Pl. : 39 (1789)

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Discussion

Diagnosis

Biology And Ecology

  • Once common on coastal cliffs, savannahs, and ravines, the species are now almost extinct in the wild, but are widely cultivated in botanic gardens where they appear to hybridise freely. Some native trees of Latania loddigesii are present on Round Island. Latania lontaroides, endemic to Reunion, is occasionally left in fields as isolated individuals whereas L. verschaffeltii, endemic and widespread on Rodrigues, is reduced to isolated individuals and a small population at Fond la Bonté above Baie aux Huîtres. There may be a few native L. loddigesii remaining on Mauritius. (J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008)A

Uses

Description

  • Moderate, solitary, mostly unarmed, pleonanthic, dioecious, tree palms. Stem erect, rough, marked with spiral, elliptic leaf scars. Leaves induplicate, costapalmate, marcescent in young individuals, abscising cleanly in trunked specimens; sheath narrow, inserted at an angle, asymmetrical, angled, with a flange toward the lower side, split horizontally at the base, smooth or densely tomentose; petiole robust, long, adaxially deeply channelled near the base, distally flattened, abaxially rounded, adaxial surface smooth, abaxial surface densely floccose, margin smooth or with a few shallow teeth; adaxial hastula short but conspicuous, triangular or rounded, abaxial hastula absent; blade divided to ca. 1/3–1/2 its length along adaxial folds into regular, stiff, single-fold segments, these shortly bifid or not, acute to acuminate, abaxial costa and ridges of folds often densely floccose, midribs prominent abaxially, transverse veinlets not evident. Inflorescences interfoliar, staminate and pistillate superficially dissimilar. Staminate inflorescence with elongate peduncle, elliptic at base in cross-section, adaxially channelled, thin distally; prophyll short, wide, tubular basally, 2-keeled, with a sharp pointed limb about equal in length to the tubular base, abaxially densely floccose; peduncular bracts 1–2–several, loosely sheathing, resembling the prophyll but with a single keel; rachis longer than the peduncle; rachis bracts like the peduncular; first-order branches short, not exceeding subtending bracts, flat, often wide, crescentic in cross-section, branched digitately at the tip to form several (1–14) rachillae; rachillae short or long, spike-like, terete, bearing short, crowded tubular bracts, each bract connate laterally with proximal and distal bracts to form a pit enclosing a single staminate flower. Staminate flowers each bearing a stiff cupular bracteole; calyx tubular basally, 3-lobed, irregularly rounded, thicker distally; corolla with a stalk-like base carrying the rest of the flower out of the pit and 3 spathulate lobes; stamens 15–30 or more, filaments short, slightly tapering, anthers basifixed, latrorse; pistillode columnar, ovarian part slightly expanded. Pollen ellipsoidal, usually slightly asymmetric; aperture a distal sulcus; ectexine tectate, perforate and micro-channelled, or rugulate, aperture margin similar; infratectum columellate; longest axis 34–50 µm [3/3]. Pistillate inflorescence with prophyll, peduncular, and first-order bracts similar to staminate, but first-order branches fewer, each bearing only 1 or 2 rachillae; rachillae wider, longer, sheathed in fewer, larger tubular bracts, lower-most and distal bracts empty, central bracts, each subtending a pistillate flower, bracts tightly surrounding base of flower but not forming pits. Pistillate flowers fewer, globose, much larger, widely spaced in a 2/5 phyllotaxy, solitary, each bearing 2 stiff, cupular, imbricate, ± connate bracteoles; sepals 3, stiff, imbricate, rounded; petals like the sepals; staminodes 6–9, connate in a low lobed cupule, vestigial anthers sometimes present; gynoecium globose, trilocular, triovulate, style expanded, stigma undeveloped, locules uniovulate but 2 lateral bodies beside the ovule, ovule orthotropous. Fruit usually developing from all 3 carpels, large, oblong or obovoid, stigmatic area apical or subapical, usually 3–(1–2)-seeded, (4 carpels often present); epicarp smooth, mesocarp fleshy, endocarp comprising 3 separate pyrenes, hard, tanniniferous, pyrenes obovoid, variously ridged and sculptured, sculpturing diagnostic for species. Seed almond-shaped, smooth, basally attached, endosperm homogeneous; embryo apical. Germination remote-tubular; eophyll digitate. Cytology: 2n = 28. (J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008)A

Anatomy

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