Araceae
Protarum Engl.
SUMMARY
HABIT : seasonally (?irregularly) dormant herbs, tuber subglobose, with numerous, very densely arranged, annular leaf scars. LEAF : solitary. PETIOLE : long, sheath short. BLADE : pedatisect to radiatisect, almost radiate, leaflets shortly stalked, elliptic to narrowly elliptic, acuminate; primary lateral veins of lobes pinnate, numerous, forming submarginal collective vein, 2 marginal veins also present, higher order venation reticulate. INFLORESCENCE : solitary, appearing with or without leaves. PEDUNCLE : short, much shorter than petiole. SPATHE : slightly constricted between tube and blade, tube convolute, shorter than blade, blade erect, boat-shaped, marcescent. SPADIX : much shorter than spathe, female zone conoid, separated from male zone by more slender sterile zone covered with narrowly elongated synandrodes or partly naked, male zone ± cylindric to obconic, terminal sterile appendix thicker, digitiform, obtuse, ± smooth. FLOWERS : unisexual, perigone absent. MALE FLOWER : synandrium 3-6-androus, sessile, subprismatic, ± excavated centrally, fused connectives broad, margins lobed, thecae broadly ellipsoid to subglobose, dehiscing by broad apical slit. POLLEN : inaperturate, ellipsoid, small (21 µm., range 20-22 µm.), exine striate. FEMALE FLOWER : gynoecium ovoid to ellipsoid, surrounded by whorl of 4-6, free, ± imbricate, thickish, oblong, subprismatic staminodes, ovary ovoid to ellipsoid, 1-locular, ovules 4, hemiorthotropous, micropyle elongate, funicle short, placenta basal, style shortly attenuate, stigma 2-4-lobed, much broader than style. BERRY : ± ellipsoid to obovoid, with persistent stigma remnant, usually 1-seeded, orange, infructescence enclosed by persistent and much enlarged spathe tube. SEED : ellipsoid-oblong, testa costate, dark brown, embryo small, flattened and disc-like, endosperm copious.