Cyphosperma H.Wendl. ex Hook.f., Gen. Pl. 3: 895 (1883)

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Description

  • Moderate, solitary, unarmed, pleonanthic, monoecious palms. Stem erect, ± prominently ringed with irregular leaf scars. Leaves regularly pinnate, or bifid or irregularly divided, ± 3-ranked, spreading or ± erect; sheaths split opposite the petiole, not forming a crownshaft, glabrous; petiole short, stout, channelled to ± flat adaxially, rounded abaxially; rachis adaxially channelled above the base, becoming nearly triangular in section with a narrow ridge toward the apex, rounded abaxially, with scales and tomentum; leaflets when present, acute, single-fold, with elevated midrib, adaxially with 2 lateral veins and many secondary veins with or without linear scales, prominently veined abaxially with deciduous tomentum, ramenta sometimes present, transverse veinlets inconspicuous. Inflorescences interfoliar but persisting below the leaves, arched in flower, pendulous in fruit, branched to 2 orders basally, to 1 order distally, branches and rachillae with a prominent pulvinus at the base, protandrous; peduncle somewhat dorsiventrally compressed and elliptical in cross-section, elongate, much exceeding the bracts at anthesis; prophyll tubular, short, incompletely encircling the peduncle abaxially, 2-keeled laterally, chartaceous, open apically, ± glabrous, marcescent; peduncular bract with tubular base, much longer than the prophyll, beaked, covered with deciduous tomentum, also marcescent; rachis bearing low, acute to rounded bracts subtending branches and rachillae; rachillae distant, slender, moderate, tomentose throughout or glabrous except for patches of stiff, pale brown hairs in the upper and lateral parts of pit cavities, bearing acute or rounded bracts subtending partially sunken triads nearly throughout the rachillae, with paired or solitary staminate flowers in the upper 1/4 or less; bracteoles surrounding the pistillate flower nearly equal, imbricate, nearly as long as the bract subtending the triad. Staminate flowers symmetrical; sepals 3, distinct, rounded, imbricate, gibbous basally and centrally keeled; petals 3, distinct, valvate; stamens 6, filaments flattened, inflexed at the apex in bud, erect at anthesis, anthers oblong, dorsifixed, briefly emarginate at the base and apex; pistillode overtopping the stamens in bud, nearly columnar, apex expanded, 3-grooved. Pollen ellipsoidal asymmetric, occasionally lozenge-shaped; aperture a distal sulcus; ectexine tectate, perforate and micro-channelled or finely perforate-rugulate, aperture margin similar or slightly finer; infratectum columellate; longest axis 29–43 µm [1/3]. Pistillate flowers larger than the staminate; sepals 3, distinct, rounded, imbricate; petals 3, distinct, imbricate except for briefly valvate apices; staminodes 3, distinct, tooth-like at one side of gynoecium; gynoecium unilocular, uniovulate, ellipsoidal, stigmas 3, recurved, ovule pendulous, form not known. Fruit broadly ellipsoidal, with stigmatic remains lateral in upper 1/4 –1/3; epicarp smooth when fresh, drying pebbled, mesocarp fleshy, with short fibre bundles nearly perpendicular to the epicarp, whitish parenchyma with dispersed, elongate, irregular tannin cells and thin, flat fibres, near but not adnate to the endocarp, endocarp thin, vitreous, fragile, irregularly sculptured, ridged, and grooved. Seed irregularly sculptured like the endocarp, hilum linear, endosperm homogeneous; embryo basal. Germination adjacent-ligular; eophyll bifid. Cytology: 2n = 32. (J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008)A

Anatomy

Fossil record

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