Alocasia macrorrhizos (L.) G.Don

Massive, pachycaul, evergreen herb to 4 m with slightly milky latex. Stem erect to ca 1.5 m, then decumbent. Leaves several to rather many together, clustered at the tips of stems of larger plants; petioles to 1.3 m long, sheathing in lower 1/3–½, medium green, less often deep purple, or with moderately well-developed pale to medium brown reptilian markings; leaf blade ovate-sagittate, bluntly triangular in general outline, to 120 × 50 cm, held more or less erect, margin entire to very slightly sinuous, concolorous, bright green on both surfaces, less often green with deep purple veins, or the whole blade coppery-brown; primary lateral veins ca 9 on each side of the anterior costa; axillary glands of primary veins distinct; secondary venation flush with the blade or slightly raised abaxially, not forming interprimary collective veins or these only poorly defined; posterior lobes ca 1/3–½ the length of the anterior, somewhat rotund, often overlapping, naked in the sinus in adult plants, weakly peltate in juveniles. Inflorescences paired among the leaf bases, subtended by membranous cataphylls; peduncle barely exceeding the cataphylls at anthesis; spathe ca 13–35 cm long, constricted about 1/6th of the way from the base; lower spathe green, ovoid; spathe limb broadly oblong-lanceolate, 10.5–29 cm long, hooded at anthesis, later reflexed, then deliquescent, membranous, pale yellow; spadix slightly shorter than the spathe, shortly stipitate; pistillate flower zone conical-cylindrical, 1–2 × ca 1.5 cm; ovaries pale green, ca 3 mm diam.; stigma sessile, 3–5-lobed, the lobes conical, yellow; sterile interstice slightly shorter than to equalling the pistillate zone, whitish, very slightly narrowed corresponding to the spathe constriction; synandrodia rhombo-hexagonal, ca 2.5 mm diam., lower ones paler, incompletely connate or with a central hole, the upper ones resembling synandria; staminate flower zone cylindrical, ca 3–7 × ca 2 cm, whitish; synandria 5–9–merous, rhombo-hexagonal, convex-topped owing to cap-forming synconnective, ca 2 mm diam.; appendix slightly thicker than the staminate zone at the base, then tapering, equalling to considerably exceeding half the length of the spadix, yellowish; fruiting spathe oblong-ellipsoid, ca 8 cm long, green; fruits ellipsoid, ca 12 × 8 mm, ripening scarlet.