Physokentia Becc., Atti Soc. Tosc. Sci. Nat. Pisa, Mem. 44: 152 (1934)

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  • Solitary, small to moderate, unarmed, pleonanthic, monoecious palms. Stem erect, ringed with leaf scars, stilt roots conspicuously developed, forming a cone supporting the stem base. Leaves pinnate, neatly abscising; sheaths tubular, forming a conspicuous crownshaft, usually bearing a dense covering of ± caducous, floccose tomentum, the mouth lacking a ligule; petiole absent or short, ± rounded, variously clothed in scales and/or tomentum; rachis variously scaly or tomentose like the petiole; leaflets regularly arranged, single-fold, acute or acuminate (or minutely lobed in Physokentia tete) or blade irregularly divided into single- or several-fold, narrow to broad, ± sigmoid leaflets, the proximal acute or acuminate, the distal, including the apical pair, shallowly lobed, the lobes corresponding to the adaxial ribs, blade adaxially glabrous or with minute, dot-like scales along the main veins, abaxially rather densely covered in minute, dot-like scales, the main ribs also bearing numerous conspicuous ramenta, transverse veinlets inconspicuous. Inflorescences solitary, infrafoliar, branching to 2 (rarely 3) orders proximally, to 1 order distally, apparently protandrous; peduncle short, winged at the base, narrow elliptic in cross-section; prophyll inserted near the base of the peduncle, open abaxially in bud, not completely encircling the peduncle at the insertion; peduncular bract inserted just above and exceeding the prophyll, completely encircling the peduncle, tubular, enclosing the inflorescence in bud, ± beaked, splitting abaxially, abscising with the prophyll at anthesis; rachis longer than the peduncle, but itself relatively short, bearing ca. 12–20, spirally arranged, first-order branches; rachis bracts inconspicuous; rachillae spreading, curved or ± pendulous, somewhat flexuous, ± angled, bearing spirally arranged triads of white to red flowers in the proximal ca. 1/3, distally bearing solitary or paired staminate flowers, rarely rachillae bearing only staminate flowers; rachilla bracts prominent, rounded to acute, often ± reflexed; bracteoles membranous, rounded, or rarely (P. dennisii) each prolonged into a slender process, sometimes ciliate-margined. Staminate flowers briefly pedicellate, ± asymmetrical; sepals 3, distinct, imbricate, ± broad, triangular, keeled, the margins often coarsely toothed; petals 3, distinct or very briefly joined at the base, valvate; stamens 6, filaments slender, elongate, prominently inflexed at the apex in bud; anthers oblong-linear, medifixed, versatile, latrorse; pistillode conspicuous, elongate, conical or columnar, ± trifid. Pollen ellipsoidal asymmetric, occasionally oblate triangular; aperture a distal sulcus, less frequently a trichotomosulcus; ectexine tectate, perforate and micro-channelled or finely perforate-rugulate, aperture margin similar or slightly finer; infratectum columellate; longest axis 33–64 µm [5/8]. Pistillate flowers ± globular, sessile; sepals 3, distinct, imbricate; petals 3, distinct, broadly imbricate with short valvate triangular tips; staminodes 3, tooth-like; gynoecium ovoid, unilocular, uniovulate, stigmas 3, short, recurved, ovule laterally attached, hemianatropous. Fruit globose or subglobose, red or black at maturity, stigmatic remains eccentrically apical; perianth whorls persistent, epicarp smooth, or drying wrinkled, mesocarp fleshy with few flat fibres and numerous sclereids, easily separated from the endocarp, endocarp thin or thick, variously angled or ridged and sculptured or almost smooth and rather fragile (P. avia), usually with a prominent adaxial keel and a sharp to obtuse abaxial ridge, operculum rounded to 4-angled. Seed conforming to the endocarp shape, laterally attached with elongate, narrow hilum, raphe branches ± horizontal, loosely anastomosing, endosperm homogeneous or ruminate; embryo basal. Germination adjacent-ligular; eophyll bifid. Cytology: 2n = ca. 32. (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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