Philodendron narinoense Croat

Hemiepiphytic vine or occasionally terrestrial; internodes elongate, 3-20 cm long, but much shorter on plant high on tree, to 3 cm diam., weakly glossy, dark green with sparse, coarse, short whitish streaks, especially at upper end; cataphylls yellow-green or green, sometimes tinged red, unribbed on younger plants, becoming sharply D-shaped, margins briefly flaring or prominently erect, 12-16 cm long, persisting semi-intact at upper nodes, soon decaying to thin, pale fibers; juvenile petioles 25-35 cm long, 2-3 mm diam.; petioles (35-) 46-55 cm long (averaging 53 cm), 3-5 mm diam. at middle, terete above base, with an obtuse medial rib beyond middle, or obtusely flattened adaxially; juvenile blades 17-28 cm long, 7-13 cm wide, with anterior lobe 15-20 cm long, 6-12 cm wide, with posterior lobes often unequal, 2-10 cm long, 3-5 cm wide, usually directed outward, with sinus 2-7 cm deep; adult blades narrowly ovate-triangular, narrowly acuminate at apex, cordate-sagittate at base, (26-) 40-46 cm long, 12-25 cm wide (averaging 46 X 23 cm), 1.7-2.3 times longer than broad, 0.7-1.0 times length of the petioles, broadest near point of petiole attachment, subcoriaceous to thinly coriaceous; upper surface dark green and matte-velvety; lower surface slightly to moderately paler and semiglossy to moderately glossy; anterior lobe (18-) 27-36 cm long; posterior lobes often markedly unequal, 9-18 cm long, 7-12 cm wide, directed outward or inward on adult plants; sinus parabolic to spathulate, occasionally V-shaped, 8-18 cm deep, 4-7 cm wide; midrib sunken or flat and paler green above, convex and paler below; basal veins 4-7 pair, 1-3 pair free to base, the remainder coalesced for 2-8 cm, narrowly sunken above, convex below; posterior rib naked for 1-4 cm; primary lateral veins 10-12 per side, departing midrib at 70°-90° angles, concave to narrowly sunken and concolorous above, round-raised to convex and matte below; minor veins visible but moderately obscure; INFLORESCENCES 1-2 per axil; peduncle white 14-15 cm long, 4-6 mm diam. on drying; spathe 13-14.5 cm long, 3 cm diam. furled, flattening to ca. 5 cm wide, the dark maroon on tube (both surfaces); blade flattening to 6 cm wide, green tinged maroon on blade yellow-green at tip and along open margin, otherwise heavily tinged maroon, inner surface reddish-violet except at apex, whitish at apex; spadix 10.7-11.5 cm long, pistillate portion, pale green, 2.1-3.7 cm long in front, ca. 1.3-2 cm long in back, 1.2 cm diam. midway; staminate portion 5.5-7.4 cm long, sterile staminate portion 0.7-2.2 cm long, 0.7-1.1 cm diam.; staminate flowers 0.9-1.2 mm long, 0.8-1.5 mm wide; sterile staminate flowers 1.5-2.2 mm long, 0.6-1.1 mm wide; pistils 1.1-1.2 mm long, 0.6-0.7 rom diam.; locules 4 per ovary; ovule 16-20 per locule.