15. Aglaonema Schott, Wiener Z. Kunst. 1829: 892. 1829.
广东万年青属 guang dong wan nian qing shu
Authors: Heng Li & Peter C. Boyce
Herbs, evergreen, sometimes robust. Stem epigeal, erect to decumbent and mostly unbranched or creeping and often branched, internodes green, becoming brown with age, smooth, often rooting at nodes when decumbent. Leaves several, forming an apical crown; petiole shorter than leaf blade, sheath usually long; leaf blade often with striking, silvery and pale green variegated patterns, ovate-elliptic or narrowly elliptic, rarely broadly ovate or sublinear, base often unequal, attenuate to rounded, rarely cordate; primary lateral veins pinnate, often weakly differentiated, running into marginal vein, higher order venation parallel-pinnate. Inflorescences 1-9 per each floral sympodium; peduncle shorter or longer than petioles, sometimes deflexed in fruit. Spathe caducous, persistent, or marcescent, erect, green to whitish, boat-shaped to convolute, not differentiated into tube and blade, ovate to ± globose, slightly to strongly decurrent, often apiculate. Spadix cylindric to clavate, shorter or longer than spathe, stipe long to almost absent; female zone rather few flowered, either separated by staminodes or contiguous with, and much shorter than, male zone; male zone fertile to apex, rarely with staminodes basally. Flowers unisexual, naked. Female flowers: ovary subglobose, 1-loculed; ovule 1, anatropous, broadly ovoid; funicle very short; placenta basal; stylar region short, thick; stigma broad, disciform, concave centrally. Male flowers: stamens free, not forming clear floral groups; filaments usually distinct, connective thickened; thecae opposite, obovoid, short, dehiscing by apical pore or reniform transverse slit. Fruit an ellipsoid berry, outer layer fleshy green but turning yellow, rarely white and finally red. Seed solitary, ellipsoid, almost as large as berry; testa thin, ± smooth; integument inconspicuous; embryo large; endosperm absent.
Twenty-one species: tropical and subtropical Asia; two species in China.
Aglaonema ovatum Engler (Bot. Jahrb. Syst. 25: 21. 1898) is abundant in N Laos next to the Chinese border and so is expected to be found eventually in SW China.
Many species are widely cultivated in gardens as evergreen ornamental plants.
