Philodendron mexicanum Engl.

Usually hemiepiphytic, sometimes terrestrial or epilithic; stem scandent, leaf scars conspicuous, 1--1.5 cm long, 1.3--1.6 cm wide; internodes scurfy, glaucous to semiglossy, 18--21 cm long, 1--2 cm diam., longer than broad, medium green to gray-green, epidermis blistering, fissured more or less transversely; roots branched at tips, sometimes with swollen nodes along length; cataphylls fleshy, 10--23 cm long, unribbed or bluntly 1-ribbed, pale green, glossy, drying yellowish tan to yellowish green, deciduous intact. LEAVES: Petioles 22--66.5 cm long, 2--13 mm diam., terete, moderately spongy, medium green, somewhat flattened adaxially, surface semiglossy; blades narrowly triangular-sagittate to triangular-hastate, subcoriaceous, acuminate to long-acuminate at apex, sagittate to hastate at base, 23--46 cm long, 14--38 cm wide (1.3--2.7 times longer than wide), (0.6--1.5 times longer than petiole), about equal in length to petiole, margins weakly undulate, upper surface dark green, drying dark brownish green, semiglossy, lower surface drying yellowish green, weakly glossy, paler; medial lobe 19--38 cm long, 8--20 cm wide (1.7--2.7 times longer than posterior lobes), usually 3--3.5 times longer than wide (rarely to 1.7 times longer than wide); posterior lobes 7--19.5 cm long, 4--12.6 cm wide, directed somewhat toward the base, rounded to rarely rounded; sinus parabolic to hippocrepiform or spathulate; midrib broadly sunken, concolorous above, convex, sparsely orange-spotted, slightly paler than surface below; basal veins 0--1(2--5) per side, with 0--1(2--5) free to base, or 1 coalesced, the third and fourth coalesced 3.6--4(13) cm; posterior rib not naked or naked for 0.5--2 cm, directed straight toward the tip of the blade and remaining 1.5--3.5 cm distant from blade margin; primary lateral veins (2)4--5(6) per side, departing midrib at a 55--65º angle, more or less straight to the margins, weakly sunken above, raised below; minor veins moderately distinct below, arising from both the midrib and primary lateral veins. INFLORESCENCES 1 per axil; peduncle 4--15 cm long, 4--12 mm diam.; spathe glossy, 8--16.5 cm long, 1.9--2.3 cm diam. (0.8--1.4(1.5--2.4) times longer than peduncle), acute at apex, the margins paler to clear within; spathe blade greenish to whitish outside; resin canals pale range and appearing as continuous lines inside; spathe tube greenish, sometimes pale reddish tinged outside; red-violet to maroon (B & K Red-Purple 5/7.5) inside; spadix sessile; bluntly rounded to somewhat acute at apex, 10.5--14.7 cm long, broadest toward the apex, constricted below the middle of fertile staminate portion; pistillate portion pale green to green to pale yellow, cylindrical to obovoid, 2-6 cm long, 1 cm diam. at apex, 1.1 cm diam. at middle, 1.3 cm wide at base; staminate portion (6.4)10.3--12.7 cm long; fertile staminate portion creamy white, more or less cylindrical, 6--17 mm diam. at base, 7--15 mm diam. at middle, 1.1 cm diam. ca. 1 cm from apex, about as broad as the pistillate and the sterile portions; sterile staminate portion usually broader than the pistillate portion, white to light gray, 1--1.2 cm diam.; pistils 1.6--2(3.5) mm long, 1.1--1.3(2.6) mm diam., transparent white; ovary 5--7-locular, 0.9--2.7 mm long, 1.2--1.4(2.3-2.6) mm diam., with sub-basal placentation; locules 0.9--1.1(2.5) mm long, 0.2--0.4(0.6--0.7) mm diam.; ovule sac 0.6--0.7 mm long; ovules 1--2(3) per locule, digitate, contained within transparent ovule sac, 0.3--0.6(1.1) mm long, longer than funicle; funicle 0.3 mm long, style 0.7(1) mm long, 1.2--1.5(2.4) mm diam., similar to style type B; style apex domed; stigma discoid, at least sometimes lobed both laterally and vertically, sometimes more or less cylindrical, 0.7--1.0 mm diam., 0.1--0.3 mm high, covering center of style apex, at least sometimes drying with radial arms sunken between the central peak and the peaks on the end of the arms (Croat & Hannon 64520); the androecium truncate, margins irregularly 4--6-sided; thecae more or less cylindrical, 0.3--0.4 mm wide, more or less parallel to one another; sterile staminate flowers bluntly or acutely 4--6-sided, 1.3--1.9 mm long, 1.3--1.8 mm wide. INFRUCTESCENCE with seeds 1 per locule, yellowish orange, 1.5--1.9 mm long, 0.6--0.8 mm diam.