Large, epiphytic; internodes short, drying 3.5 cm diam., yellow-brown, coarsely and irregularly acute-ridged; cataphylls not seen, but promptly deciduous. LEAVES: Petioles to ca. 1 m long, subterete near apex, drying narrowly and deeply sulcate toward the based, broadly flattened near the base, finely to coarsely ribbed abaxially, drying dark reddish brown, matte; blades deeply 3-lobed, 72 × 75 cm, subcoriaceous, drying dark yellowish gray-brown above, paler and reddish brown below; medial lobe 51.5-57.5 × 30-40 cm; posterior lobes 32-41 × 17.5- 26 cm, spreading laterally, the lower margin straight or prominently sinuate; basal veins 18 pairs, the 1st pair free to the base, the remaining variously united into a posterior rib which extend straight to the tip of the blade, 11-12 veins basioscopic, 7 acroscopic; midrib broadly convex and slightly paler above, more nearly convex and finely ribbed below, drying yellow-brown and paler than the surface; primary lateral veins 5-7 per side, arising at 60-70° angle; minor veins drying weakly raised, concolorous, arising from both the midrib and the primary lateral veins. INFLORESCENCE: 5 per axil, white, drying dark red-brown; peduncle 5-8.5 cm long, drying flattened, 3 mm diam., finely ridged; spathe white, 12.5-17.5 × 2-3 cm on drying, matte, minutely granuliform and covered sparsely with minute white globular protrusions (not capable of being scraped free without disintegrating); spadix 15.6 cm long; pistillate portion 7.2 cm long; staminate portion 8.6 cm long; pistils 2 × 1 mm on drying; style 1.2 mm diam., drying pale brown; 0.8-0.9 mm diam.; locules 5; ovules 1 per locule.
This new species is characterized by deeply 3-lobed blades that are dark brown on the upper surface and dark yellow-brown on the lower surface with major veins convex on the lower surface. The spathe is white and the peduncles dry slender and blackened. It is closely related to P. brent-berlinii Croat, which shares similarly deeply 3-lobed blades with prominent lateral auricles. Philodendron brent-berlinii differs in having blades that dry yellowish gray on both surfaces and major veins that dry bluntly acute on the lower surface. Philodendron brent-berlinii also differs in having the spathe tinged orange or reddish brown with the peduncles thicker.