Wallaceodoxa Heatubun & W. J. Baker, Kew Bull. 69: 9525 (2014)

Primary tabs

no image available

Distribution

Map uses TDWG level 3 distributions (http://www.nhm.ac.uk/hosted_sites/tdwg/geogrphy.html)

Description

  • Moderately robust, solitary, unarmed, pleonanthic, monoecious emergent tree palm. Stem erect, moderate, roughly fissured, whitish brown, nodes inconspicuous. Leaves pinnate, pendulous, crown hemispherical in outline; sheath tubular, forming well-defined crownshaft, glabrous adaxially except for scattered patches of white floccose indumetum, abaxially with thick, white, caducous, lanate indumentum composed of very fine translucent fibres mixed with a lesser proportion of similar brown fibres, interspersed with numerous, large, brown-black twisted hairs that are more abundant near the sheath mouth and junction with petiole; petiole elongate, slender, channelled adaxially, rounded abaxially, with dense indumentum as on the sheath; rachis somewhat slender, arching, forming a ridge adaxially, rounded abaxially, with indumentum as on the sheath, but with the large, brown-black twisted hairs more numerous; leaflets regularly arranged, subopposite to alternate, pendulous, borne on adaxial surface of rachis on the slope of the ridge, forming a sharp-angle, single-fold with inconspicuous main vein, green, slightly discolorous when dried, paler adaxially, darker and glaucous abaxially, papery, basal leaflets linear to lanceolate or slightly sigmoid, tips inconspicuously praemorse, sometimes with persistent, pendulous remains of the rein, middle leaflets elongate, somewhat lanceolate, tips obliquely and inconspicuously praemorse, apical leaflets paired or solitary, tips truncate and unevenly praemorse or toothed. Inflorescence infrafoliar, protandrous, branching to 3 orders (rarely to 4 orders?), divaricate; peduncle elongate, rather flat, slightly elliptical in cross section, shorter than rachis, light green to cream with abundant light brown to dark brown indumentum; prophyll caducous, lanceolate, 2-keeled, papery, cream to light green, entirely enclosing the inflorescence, then splitting longitudinally when inflorescence expanding and falling before staminate anthesis; first peduncular bract caducous, elongate, papery, cream to light green, with abundant lanate indumentum scattered on surface; remaining inflorescence bracts reduced to inconspicuous, horizontal, scar-like grooves; rachis light green to cream; the basalmost primary branch relatively long, branched to few second orders branches and then rachillae, primary branches widely spaced; rachillae numerous, fleshy, slightly sinuous near the tip, glabrous, floral triads densely arranged. Staminate flowers small to moderate, elongate, bullet-shaped in bud, symmetrical, whitish cream to greenish white; sepals 3, distinct, strongly imbricate, rounded; petals 3, valvate, united at the base, elliptic, tip slightly rounded, thick and fleshy, somewhat striate, light green to cream; stamens numerous, 58 ? 64, variable in length, filaments awl-shaped, much longer than anther, white to cream; anthers sagittate, latrorse, cream-coloured; pistillode shorter than the stamens, irregularly ellipsoidal, lobed, cream to dark brown. Pistillate flowers slightly smaller than the staminate, ellipsoid, light green to cream, with conspicuous stigma at anthesis; sepals 3, strongly imbricate, keeled, rounded, somewhat asymmetrical, thicker at the base; petals 3, strongly imbricate, elliptic, somewhat striate; staminodes few, inconspicuous, membranous, triangular, cream to light brown; gynoecium ellipsoidal, light green to cream, stigma trifid, white at anthesis; ovule basal. Fruit ellipsoidal, stigmatic remains apical, persistent, black, perianth persistent; epicarp smooth, shiny, thin, light green when immature, turning yellow, orange to red when mature; mesocarp fibrous, fleshy, mucilaginous, tanniniferous, with slender to large fibres and sclerified ground tissue surrounding the endocarp; endocarp very thin, cartilaginous, fragile, terete, lacking any grooves or angles, straw-coloured, with numerous flat adherent fibres; seed broadly ellipsoid, without any grooves or angles, round in cross-section; hilum elliptical, elongate, stretching from base to apex; raphe branches anastomosing; endosperm deeply ruminate; embryo basal, white. (C.D. Heatubun, S. Zona & W.J. Baker - Three new genera of arecoid palm (Arecaceae) from eastern Malesia in Kew Bull.. 2014)A