Philodendron burgeri Grayum

Slender-stemmed vine climbing to at least 10 m on trunks the branches mostly pendent, the inflorescences arching upward. Internodes 0.3-6.6 cm long, 0.25-0.60 cm wide, green to gray-green, matte, weakly striate (epidermis of young stems thin brittle, and cracking), drying tan to dark brown, coarsely sulcate. LEAVES: Petiole (4.9-) 5.2-10.4 cm long, P/L=0.31-0.51 (-0.53), extensively sheathed, the sheath involute at base otherwise horizontally spreading and at least sometimes resolute adnate or with free portion prolonged apically to ca. 0.6 cm; unsheathed portion of petiole 0.1-0.5(-0.7) cm long, sulcate above with the margins sharp. Lamina (9.7-) 13.0-21.6 cm long, (2.9-) 3.7-9.6 cm wide, L/W= (2.11-) 2.39-3.61 (-3.87), IQI= (1-) 2-8 (-12) membranous, weakly glossy to semiglossy above, matte be- low, weakly to moderately bicolored narrowly lanceolate to narrowly ovate, narrowly to broadly elliptical, or oblanceolate (usually broadest at or below the middle), abruptly or sometimes gradually acuminate apically (the acumen 0.7-1.7 cm long), cuneate to rounded or subtruncate basally; midrib sunken above convex below; primary lateral veins 5-7 (-10) per side, (0.5-) 1.0-3.9 cm apart, obscurely sunken above weakly convex below those in the apical 1/3-1/2 generally indistinct; minor veins visible below darker; abaxial laminar surface drying without granules, or sparsely to moderately but obscurely granular, alveolate the reticulate veins obvious but not prominent; white stitching and resin canals sometimes evident (the stitching following the canals where both are visible); adaxial surface very smooth to sparsely or moderately and usually obscurely granular densely and evenly alveolate the reticulate veins few (most evident toward margins); no stitching or resin canals, except rarely toward the distal margins. INFLORESCENCES always solitary; cataphylls absent; peduncle (1.0-) 1.6-2.4 cm long, P/S=ca. 0.12-0.13; spathe at anthesis ca. 7.9-15.4 cm long (to 16.5+ cm post anthesis), 1.5-3.2 cm wide (to 3.9+ cm post anthesis) externally green below, yellowish green to whitish green distally, internally uniformly yellow-green (purple streaking at base of spathe with mottling of purple where spathe joins base of spadix,'' Burger et al. 12333); spathe drying sparsely to moderately but obscurely granular and ± densely short white-lineate externally, internally sparsely and obscurely granular, densely and minutely alveolate and moderately white-lineate, with longitudinal secretory striations to ca. 3/5 to apex; acumen of spathe 0.4-2.5 cm long. Stipe of spadix 0.4-0.5 cm long, adnate to spathe; spadix 8.6-13.6 cm long (to 14.4+ cm post anthesis), the fertile male portion 0.7-0.9 cm wide, white; sterile male zone 0.6-0.7 cm long; female portion of spadix 1.9-3.4 cm long (to 7.2+ cm in fruit), F/S=ca. 0.22-0.25, ca. 1.2 cm wide (to 3.7+ cm in fruit); fertile male flowers (1.1-) 1.5-2.3 mm long, 0.6-1.1 mm wide, irregularly polygonal, columnar; sterile male flowers 2.6-3.0 mm long, 1.3-1.4 mm wide, fungoid; female flowers (1.3-) 1.9-2.5 mm long, 0.6-1.1 mm wide, the stylar canals 3-4 (-5). INFRUCTESCENCES: Ripe fruits "de color crema" (Obando 68). Seeds ca. 0.9-1.2 mm long, 0.20-0.30 mm wide, ± straight to sigmoid, finely striate with the striae minutely cancellate, drying light brown and glossy.