Philodendron rhizomatosum Sakuragui & Mayo

Terrestrial herb. Stem: greyish, internodes 0.2-0.5 cm long. Prophyll 6.5-12.5 x 1.5-2.5 cm, triangular to narrowly triangular, red to reddish-vinaceous becoming chestnut-coloured. LEAVES: Petiole 41-75 cm long; leaf blade 15.5-17 x 13.5-16.5 cm, broadly ovate to circular, apex acuminate, base cordate, distinctly paler on lower surface, chartaceous to subcoriaceous; anterior division 11-21 x 13-20 cm, primary lateral veins 4-5 per side, interprimary veins distinct; posterior divisions 5-6.5 x 7-9 cm, acroscopic veins 2-3 per side, basiscopic veins 0-2 per side; basal veins 1-4, 2 of these coalesced 0.8-1 cm; posterior rib naked for 0.5-0.8 cm. INFLORESCENCE: 1 per floral sympodium, peduncle 21-25 cm long. Spathe 9-11 x 3-3.8 cm long, ovate, not constricted, outside green with vinaceous grooves, inside white with reddish-vinaceous base. Spadix 7-9 cm long, male zone 5.5-7.5 cm long, cream; intermediate sterile zone 0.7-1 cm long, white; female zone 2.5-3.5 cm long, greenish-cream. Flowers: stamens 1.6-1.8 x 0.7-1 mm, staminodes 1.6-2 x 0.8-1.5 mm; gynoecium 2-2.6 x 2-2.8 mm, obovoid, ovary 7-9-locular, ovules 2-3 per locule, placentation sub-basal. INFRUCTESCENCE: Berries 3.5-5 mm long, pale cream becoming maroon, broadly oblong, seeds 1.6-2.0 mm long, fusiform.