Hemiepiphytic; stem scandent; internodes 3–9 x 0.4–5 cm, longer than broad, green to olive to light brown, striate, epidermis with longitudinal ridges, flaking, drying yellowish tan, sap red; roots few per node, reddish brown; cataphylls 13–18 cm, sharply 1- ribbed, sometimes with a second weak rib, bright white, drying reddish brown, deciduous when intact. LEAVES spreading; petioles 15–21 cm x 3–5 mm (dry), terete, obtusely flattened adaxially, broadly sulcate at base for 2–4 cm, light to medium green, drying dark olive-green; geniculum ca. 1 cm, drying dark brown and shrivelled; blades ovate, coriaceous to subcoriaceous, slightly bicolorous, mucronate or sometimes acuminate at apex, cordate at base, 14.5– 25 x 11–19 cm, 1.3–1.5x longer than wide, 0.9– 1.2(–1.4)x longer than petiole, margins rounded, adaxial surface semiglossy, medium green, drying glossy dark olive-green, abaxial surface paler, drying glossy and paler; anterior lobe 11.5–19 x 11–19 cm, 2.4–2.7x longer than posterior lobe, broadest close to middle; posterior lobe 4.3–8 x 5–8.5 cm, rounded; sinus parabolic to spatulate, 3–5.5 cm deep; midrib broadly convex and paler than surface adaxially, convex and paler than surface abaxially; primary lateral veins 2 to 4 per side, 2–3.8 cm apart, spreading from midrib at 60º angles, down-turned at midrib, curving broadly out to margins, weakly sunken adaxially, weakly pleated-raised abaxially; basal veins 3 to 4 pairs per side, with 1 free to base, 2 to 3 coalesced to 2.5 cm, posterior rib naked to 1 cm; minor veins moderately obscure, arising from midrib. INFLORESCENCES 3 to 6 per axil; peduncle 3.5– 6.5 cm x 3–6 mm (dry), shorter than petiole, light green, sometimes speckled with red, clearly demarcated from spathe; spathe 4–5 cm, semiglossy, constricted above tube; spathe blade 2–2.5 cm, outside white to yellow-white, inside white; spathe tube 2–3 cm, outside reddish maroon, inside white to cream; spadix protruding forward at anthesis, sessile, 3–4.8 cm; pistillate portion pale green, cylindrical to slightly clavate, 1.3–2 cm x 7–8 mm at widest point (dry); staminate portion oblong, creamy white, 2.3–3.2 cm long, narrower than pistillate portion; sterile staminate portion ca. 3 mm; pistils ca. 0.6 mm diam.; ovary 4- to 5-locular, ovules with basal placentation, 1 per locule. INFRUCTESCENCE unknown.
The species belongs to subgenus Philodendron, section Macrobelium, subsection Macrobelium, series Macrobelium and is distinguished by scandent stems with long internodes, bright snowy white cataphylls, terete petioles, and blades that are ovate and mucronate at the apex with few primary lateral veins. Also characteristic are the small inflorescences in axillary clusters that have spathes with reddish maroon tubes, and creamy white blades. Another species occurring at Bajo Calima, Philodendron hederaceum (Jacquin) Schott, might easily be mistaken for P. dryanderae, especially when sterile. The former species differs in having a smooth stem epidermis, green cataphylls, a leaf blade margin that often becomes slightly concave toward the apex, and large (9–17 cm long), solitary, green inflorescences. Philodendron dryanderae also could be confused with P. purpureoviride Engler, which has not been collected at Bajo Calima, but is known from the departments of Chocó and Nariño, Colombia. The latter species is similar in habit, blade shape, and venation, but differs in having cataphylls that are generally green and heavily tinged with maroon, and large (11–15 cm long), solitary inflorescences. Another species that could be confused with Philodendron dryanderae is P. sulcicaule Croat & Grayum, although this species is known only from Costa Rica and Panama. It is similar to P. dryanderae in habit, stem characteristics, leaf blade shape, and small, clustered inflorescences. However, it differs in having green to pink cataphylls, a leaf blade that is more triangular than ovate, obscure primary lateral veins, and inflorescences with spathe tubes that are red or purple inside.