Dracontium nivosum (Araceae)
Tuber hemispherical or rounded, 6-12cm diam., 4-8cm thick, flat above, rounded and white to brown below, 6-27cm below ground level; tubercles few, rounded, 0.8-1.5cm diam., borne around the periphery of tuber, roots white, 2-3mm diam.; cataphylls 1 to 3, 9-28 × 2-3cm, light brown, reaching or surpassing ground level. Leaves solitary; petioles 1-2m long above ground, 2.5-3cm diam. at midpoint, dark green, contrastingly mottled with dirty white or pale green blotches and forming a reptilian pattern, usually smooth in upper half and with irregular protuberances in lower half; juvenile blade sagittate, or sagittately lobed; mature blade spreading horizontally, 0.8-1m diam., often thinly coriaceous, rarely fenestrate, sometimes variegated (along the veins), without raphide cells or dark markings, matte and medium green above, matte and pale green below; middle division twice trichotomously branched (often), 30-45 × 20-40cm, with terminal subdivision consisting of 3 sections, with each basal subdivision consisting of many segments; lateral divisions twice dichotomously branched, 28-45 × 30-45cm, with terminal sub-division consisting of 2 sections, with basal sub-division consisting of many segments; terminal and subterminal sections free, each consisting of many segments; broadly oblanceolate, more than 5cm wide on each side of the major ribs, ovate or oblanceolate, mostly free from each other in each division, often with contrastingly smaller rounded or triangular segments alternating with larger segments; apices acuminate; ultimate segments 6-8cm long, often confluent with penultimate segments; other segments 5-12cm long; penultimate segments free from subterminal sections; medial segments free from basal subdivisions; basal segments present, free from each other; rachises patterned similar to petiole but in much paler shades, with spiny projections; tertiary veins obscure above, or conspicuous below; bracteoles 3 or 4, 2-28 × 1-2cm wide, light brown, the longest one ± as long as the peduncle, reaching the spathe. Inflorescence solitary, appearing before new leaf; peduncle 0-2cm long above ground, 1-1.5cm diam. at midpoint, often almost completely subterranean, scarcely mottled, whitish tinged pink, smooth; spathe 28-35 × 6-10cm, cymbiform, cucullate, arching to 45o, apex acuminate; inner surface semiglossy, maroon, with translucent area obscure; outer surface maroon, matte; margins entire, broadly overlapping in the lower half; veins obscure inside and raised outside, similar to the spathe in color; spadix hidden, stipitate, cylindric, purple or brown-purple, (3-)5- 6.5cm long, 1.2-1.5cm diam. at anthesis, never with appendages at apex; stipe 0.6-1.2cm long, 0.5-1cm diam. at anthesis. Flower tepals 5 to 8, 2.5-3mm long, 1-2mm wide, purple; stamens 6 to 8; filaments 2-2.5mm long; anthers 0.5-1mm long, slightly exserted; ovary 3-locular; stigma 3- lobed; style 4-5.5mm long above tepals, purple, persistent. Infructescence with spadix 12-18cm long, 3-3.5cm diam. in fruit; berries 3- or 4-seeded or sometimes 2-seeded, 0.8-1cm diam., 0.8-1cm thick, subglobose, 3- to 6-angular, apically truncate; mature berries orange (tinged red), with abundant raphide cells; seeds 0.5-0.7 cm diam., reniform or rounded, light brown, laterally raised; dorsal ridges obvious, 3, continuous, less than 0.5mm thick, 0.1mm high, finely decorated with small cells on both sides.
Dracontium nivosum is characterized by its subterranean peduncle with a strongly hooded and cymbiform spathe, a spathe much larger than that of any other member of the genus possessing subterranean peduncles. Other species with peduncles at least sometimes subterranean such as D. amazonense, D. bogneri, D. dubium, D. grayumianum, D. polyphyllum, D. prancei, D. purdieanum, D. soconuscum and D. ulei have spathes only 3-15(18)cm long, whereas the spathe is 28-35cm long for D. nivosum. Other species that, like D. nivosum, have the spadix hidden at anthesis owing to the broadly overlapping spathe base include D. amazonense, D. bogneri, D. prancei, and D. ulei, but none of them have ranges overlapping that of D. nivosum.
Dracontium nivosum is endemic to Para and Maranhao, Brazil.
It occurs in Tropical moist forest (T-mf) and Tropical wet forest (T-wf) life zones (Holdridge et al., 1971))
Common names attributed to snakes obviously refer to the reptilian pattern exhibited by the petioles. Perhaps for the same reason many species of Dracontium are used by native populations for snakebite remedies (Croat, 1994)