Zamioculcas Schott

HABIT : seasonally dormant or evergreen herbs with short, very thick rhizome. LEAVES : few to many, erect, leaflets deciduous during dormancy leaving persistent petiole. PETIOLE : terete, base greatly thickened and succulent, geniculate at apex, sheath ligulate, free almost to the base, very short, inconspicuous. BLADE : pinnatisect, leaflets oblong-elliptic, thickly coriaceous, capable of rooting at base once shed and forming new plants; primary lateral veins of each leaflet pinnate, running into marginal vein, higher order venation reticulate. INFLORESCENCE : 1-2 in each floral sympodium, held at ground level. PEDUNCLE : very short. SPATHE : entirely persistent to fruiting stage, slightly constricted between tube and blade, green without, whitish within, tube convolute, blade longer than tube, expanded and horizontally reflexed at anthesis. SPADIX : sessile, female zone subcylindric, separated from male zone by short constricted zone bearing sterile flowers, male zone cylindric, ellipsoid to clavate, fertile to apex. FLOWERS : unisexual, perigoniate; tepals 4, in two whorls, decussate. MALE FLOWER : tepals subprismatic, apex thickened, stamens 4, shorter than tepals, filaments free, oblong, thick, somewhat flattened, anthers introrse, connective slender, thecae ovate-ellipsoid, dehiscing by apical slit, pistillode clavate, equalling tepals. POLLEN : extruded in strands, extended monosulcate to perhaps fully zonate, ellipsoid, large (mean 60 µm.), exine thick, fossulate-foveolate, apertural exine verrucate. STERILE FLOWERS : each consisting of 4 tepals surrounding a clavate pistillode. FEMALE FLOWER : tepals strongly thickened apically, staminodes lacking, gynoecium equalling tepals, ovary ovoid, 2-locular, ovules 1 per locule, hemianatropous, funicle short, placenta axile near base of septum, style attenuate, stigma large, discoid-capitate. BERRY : depressed-globose with furrow at septum, 1-2-seeded, surrounded by persistent tepals, white, infructescence ellipsoid. SEED : ellipsoid, testa smooth, brown, raphe conspicuous, embryo large, rich in starch, endosperm nearly absent, present only as a few cell layers at chalazal end.