Acoelorrhaphe H.Wendl., Bot. Zeitung (Berlin) 37: 148 (1879)

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  • Moderate, armed, clustered, pleonanthic, hermaphroditic palm. Stem slender, erect, clothed with persistent leaf sheaths and petiole bases, older stems naked below, internodes very short. Leaves rather small, induplicate, very briefly costapalmate; sheath disintegrating into an interwoven mass of coarse, rich brown fibres; petiole moderate, slightly channelled or flattened adaxially, rounded abaxially, fiercely armed with robust, triangular, reflexed or inflexed spines, adaxial hastula conspicuous, irregularly lobed, abaxial hastula a low ridge; blade nearly orbicular, relatively flat regularly divided to below the middle into narrow, single-fold, deeply bifid, stiff segments, usually silvery abaxially due to small scales, midribs prominent abaxially, transverse veinlets conspicuous. Inflorescences slender, solitary, interfoliar, exceeding the leaves, branched to 4 orders; peduncle slender, elongate, elliptical in cross-section, usually erect; prophyll short, partly to completely enclosed by the leaf sheaths, tubular, 2-keeled laterally, splitting apically into short, irregular lobes; peduncular bracts 2, like the prophyll but much longer and more shallowly keeled; rachis about as long as the peduncle, ± glabrous, completely sheathed by tubular bracts, other branches densely tomentose; rachis bracts like the peduncular bract but smaller and decreasing in size distally; first-order branches bearing a 2-keeled membranous prophyll ± included within the primary bract; subsequent bracts very inconspicuous, triangular, membranous; rachillae slender, bearing spirally arranged, minute bracts each subtending a low spur bearing a cluster (cincinnus) of (1)–2–3 flowers, each flower subtended by a small thin bract. Flowers cream-coloured; sepals 3, fleshy and slightly connate basally; petals 3, united in a basal tube for 1/4 their length; stamens 6, borne at the mouth of corolla tube, filaments connate in a shallow cup at the base, free portions abruptly narrowed to a filiform apex, not inflexed in bud; anthers dorsifixed, short, rounded, versatile at anthesis, latrorse; gynoecium of 3 glabrous, follicular carpels, connate in stylar regions, ovule basal, erect, anatropous. Pollen ellipsoidal, with slight to obvious asymmetry; aperture a distal sulcus; ectexine tectate, finely perforate, perforate, micro-channelled, and slightly rugulate, aperture margin slightly finer; infratectum columellate, longest axis 29–33 µm [1/1]. Fruit small, rounded, developing from 1 carpel, black, stigmatic scar apical, abortive carpels basal; epicarp smooth, mesocarp thinly fleshy with prominent longitudinal fibres, endocarp thin, crustaceous. Seed with basal hilum, endosperm homogeneous penetrated by a thin intrusion of the seed coat at one side; embryo lateral near base on the antirapheal side. Germination remote-ligular (Chavez 2003); eophyll simple, narrow, lanceolate. Cytology: 2n = 36. (J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008)A

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