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Araceae
Dracontium grayumianum G.H.Zhu & Croat
SUMMARY
Tuber hemispherical, 10-18cm diam., 6-10cm thick, flat above, rounded and white to brown below, 10-20cm below ground level; tubercles few, cylindrically elongated, 0.8-1.2cm diam., 1-3cm long, borne around the periphery of tuber; roots white to 0.4cm diam.; cataphylls 3, 10-30 × 5-8cm, white or pink and light brown, 5-15cm long above ground. Leaves solitary; petioles 1-2.2m long above ground, 2-6cm 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, 1-1.5m diam., papyraceous, sometimes fenestrate, never variegated, sometimes with abundant raphide cells and dark markings, glossy and dark green above, semiglossy and medium green below; middle division 3 times or more trichotomously branched, 0.8-1 × 0.7-1cm, with terminal subdivision consisting of 3 sections, with each basal subdivision consisting of many segments; lateral divisions 3 times or more dichotomously branched, 0.85-1 × 0.7-1.1cm, with terminal subdivision consisting of 2 sections, with basal subdivision consisting of many segments; terminal and subterminal sections free, each consisting of many segments; leaf segments bilobed, broadly oblanceolate, more than 5cm wide on each side of the major ribs, lanceolate, mostly free in each division, often with contrastingly smaller rounded or triangular segments alternating with larger segments; apices acuminate, or acute, or caudate (rarely); ultimate segments 12-15cm long, confluent with penultimate segments (often); other segments 6-16cm 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 conspicuous above, or weakly raised below; bracteoles 5-15(-35)cm long, 2-3(-5)cm wide, light brown, the longest one longer than the peduncle, covering the basal half or more of the spathe (often). Inflorescences solitary or sometimes two, appearing before new leaf; peduncle 1-10(-30)cm long above ground, 1-1.8cm diam. at midpoint, often almost completely subterranean, scarcely mottled, whitish tinged pink or gray or whitish green, smooth; spathe (6-)9-15 × 2.5-4cm, non-cymbiform, constricted at a certain point and differentiated into a proximal tube and a distal lamina (blade), cucullate, arching 45o-90o, apex acuminate; 2.5-3 × 2-3 cm at widest point; lamina similar to the tube in length, or 3 to 5 times longer than the tube; inner surface semiglossy, maroon, with translucent area obscure; outer surface maroon or olive-brown, matte; margins entire, broadly overlapping at the base; veins obscure inside and raised outside (slightly), conspicuously darker or paler than the spathe, purple; spadix exposed, stipitate, cylindric, brown or purple, 2-3.5 × 0.8-1.3cm at anthesis, sometimes with one to a few appendages at apex, 0.3-0.5cm long when present; stipe 0.5-2cm long, 0.5-1.5cm diam. at anthesis, brown. Flower tepals 5 to 7, 1-4mm long, 0.5-1mm wide, light brown; stamens (5)6 to 8; filaments 3mm long; anthers 1mm long, slightly exserted; ovary bilocular, pale green; stigma 2-lobed; style 1-2mm long above tepals, dark purple, persistent. Infructescence with spadix 8-15cm long, 3.5-5.5cm diam. in fruit; berries 4-seeded, 1-2cm diam., 1-1.2cm thick, narrowly clavate, apically truncate; young berry light green; mature berry orange, with or without some reddish dots or raphide cells; seeds 0.8-1cm long, 0.6-0.7cm wide, reniform, light brown, laterally flattened; dorsal ridges obvious, 5 to 6, strongly interrupted, monomorphic, less than 0.5mm thick, 1.5-2mm high, smooth on both sides.