Podococcus G.Mann & H.Wendl., Trans. Linn. Soc. London 24: 426 (1864)

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Discussion

Diagnosis

Biology And Ecology

Etymology

Description

  • Small, colonial, unarmed, acaulescent or erect, pleonanthic, monoecious palms. Stem erect, slender, reed-like, or subterranean, covered in reddish-brown fibrous leaf bases, eventually bare and ringed with leaf scars, axillary stolons present basally and extending horizontally and eventually vertically, developing roots, and becoming new shoots; prop roots with pneumatophores developed basally. Leaves few, marcescent, pinnate, the first leaves on new shoots undivided, elliptical, pinnately ribbed, margins toothed, apex very shallowly bifid; sheath tubular, becoming split opposite the petiole, margins fibrous; petiole very slender, narrowly channelled adaxially, rounded abaxially, with dot-like scales and deciduous tomentum; rachis like the petiole but longer, tapering, extending through the terminal, often minutely bifid leaflet; leaflets rhombic, single-fold, basal half of each leaflet wedge-shaped with smooth margins, the upper half triangular, margins doubly toothed, 5 large ribs divergent from the base, midrib not evident, blade glabrous adaxially, densely covered with slender, bulbous-based, tanniniferous hairs abaxially, transverse veinlets not evident. Inflorescences solitary, interfoliar, spicate, erect at first, pendulous in fruit, protandrous; peduncle very slender, with deciduous tomentum; prophyll basal, tubular, 2-keeled, disintegrating into long fibres; peduncular bracts 2–3, inserted at wide intervals above the prophyll, tubular, disintegrating as the prophyll; rachis about as long as or longer than the peduncle, bearing spirally arranged triads of flowers basally, paired or solitary staminate flowers distally, flowers enclosed in pits; rachis bracts subtending the triads evident only as raised, curved lower margins of the pits, densely covered in stellate hairs between and inside the pits; floral bracteoles membranous, irregular, mostly pointed. Staminate flowers ± adaxial to the pistillate; staminate sepals 3, distinct, somewhat keeled dorsally, tips irregular or rounded, imbricate basally; petals 3, valvate, about twice as long as the sepals, at anthesis adnate about 2/3 their length to a solid receptacle, nearly equalling the depth of the pit, distinct lobes exserted, spreading; stamens 6, in 2 whorls, the outer opposite the sepals and shorter than the inner antepetalous whorl, filaments awl-shaped, rather short, incurved distally, anthers short, dorsifixed near the base, latrorse, connective tanniniferous; pistillode short, briefly 3-lobed. Pollen ellipsoidal, with slight or obvious asymmetry; aperture a distal sulcus; ectexine tectate, finely perforate, perforate and micro-channelled, or perforate-rugulate, aperture margin slightly finer; infratectum columellate; longest axis 27–32 µm [1/1]. Pistillate flower symmetrical; sepals 3, distinct, irregular, variously notched distally, about half as long as the petals, imbricate; petals connate and adnate basally 1/3 to 1/2 their length to a solid receptacle, nearly equalling the depth of the pit, apices imbricate in bud, spreading at anthesis; staminodes 6 (according to Mann and Wendland 1864), minute; gynoecium ovoid, trilocular, triovulate or 2 locules abortive, style not evident, stigmas 3, short, recurved at anthesis, ovule pendulous. Fruit long, ellipsoidal or with ellipsoidal lobes, often slightly curved, bright orange, 1–3-seeded, stigmatic remains central in 3-seeded fruits, lateral in 1–2-seeded fruits, the base briefly stalked, lobes developing horizontally to the floral axis; epicarp thin, smooth, rather leathery, mesocarp gelatinous with an internal layer of fibres ±adherent to the seed, endocarp crustaceous. Seed ellipsoidal, basally attached, hilum basal, raphe branches anastomosing from the base, endosperm homogeneous; embryo lateral near the middle, (?)± basal relative to the plane of the seed. Germination adjacent-ligular; eophyll rhombic, undivided, minutely bifid, toothed above the middle. Cytology not known. (J. Dransfield & N. Uhl & C. Asmussen & W.J. Baker & M. Harley & C. Lewis, Genera Palmarum. The evolution and classification of palms. 2008)A

Anatomy

  • Silica bodies of stegmata spherical, central vascular bundles of petiole with two phloem strands (Parthasarathy pers. comm.); root (Seubert 1998a, 1998b); sepals of both staminate and pistillate flowers usually lacking a vascular supply or rarely second sepal in pistillate flower with 1–2 small fibrous bundles; petals with 4–5 parallel bundles in pistillate and about 9 parallel bundles in staminate flowers; stamens each with a single trace; in young gynoecium, carpels connate with a distal septal nectary and the pistillode also apparently secretory; each carpel with 1 dorsal and 2 ventral bundles and a pendulous ovule with two integuments (Uhl unpublished). (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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