Philodendron basii Matuda,

Anales Inst. Biol. Univ. Nac. Méxic. 32: 153, Fig. 8. 1961. TYPE: Mexico. Mexico: Barranca de Malinaltenango, NE (published as SE) of Zacualpan, 1200 m, 18E43'N, 99E36'W, Matuda 37244 (holotype, MEXU). Figures 76, 81--84.

Almost always terrestrial, or trailing over rocks; stem green, stout, succulent, leaf scars conspicuous, 2--4 cm long, 4--5 cm wide; internodes 1--4 cm long, 2.5--7 cm diam., broader than long, drying olive-green, epidermis peeling, light brownish, roots long, 5 mm diam., light reddish tan; cataphylls 20--28 cm long, weakly to sharply 2-ribbed, medium green with darker ribsand dark green speckles in lower one-half of cataphyll, drying tannish, persisting intact, eventually deciduous; petioles 22--70 cm long, 8--15 mm diam., terete, medium green, surface dark striate; blades ovate-cordate, drying moderately thin, weakly bicolorous, semiglossy, acute at apex, cordate at base, 16--56 cm long, 9--38 cm wide (1.5--1.8 times longer than wide), (0.7--0.9 times the petiole length), broadest at or above middle; upper surface medium green, weakly glossy, drying medium yellow-brown;, lower surface slightly paler, semiglossy, drying yellow-green to yellow-brown; margins sinuate or weakly undulate; anterior lobe 35--48 cm long, 37.5--46 cm wide (2.5--8.5 times longer than posterior lobes); posterior lobes 4--19 cm long, 18--23 cm wide, directed inward, rounded to obtuse at apex; sinus spathulate, 10--13 cm deep; midrib weakly sunken to flat, heavily dark green striate, paler than surface above, convex, sparsely dark-lineate, paler than surface below; basal veins 3--6 per side, with 1 pair free to base, the third through fifth coalesced 3--3.5(4) cm; posterior rib naked for 1--2.5 cm; primary lateral veins 4--7 per side, departing midrib ata 40--60E angle, more or less straight to the margins, sunken and paler than surface above, convex and paler than surface below; interprimary veins sunken and concolorous above, flat and darker than surface below; branches of primary lateral veins more or less ruffled-sunken and concolorous above, raised and paler than surface below; minor veins predominately arising from the primary lateral veins, those arising from the midrib seem to disappear soon after leaving the midrib. INFLORESCENCES probably 1 per axil; peduncle 7--8 cm long, 7--8 mm diam., green; spathe 12.6--13.7 cm long, (1.7--1.8 times longer than peduncle), apiculate at apex; spathe blade pale green or white, tinged red near base outside, 8 cm long, white tinged with red near base, pale-speckled inside; spathe tube ellipsoid, dark green outside, 6 cm long, 3 cm diam., maroon-red (B & K Red-Purple 10/3) inside, spadix sessile; tapered, 11.8--12 cm long, broadest at the base; pistillate portion cylindrical, 2.5--3.8 cm long, 1.5--1.9 cm diam. midway, slightly narrower on both ends; staminate portion 7.6--13 cm long; fertile staminate portion clavate, 9--15 mm diam. at base, 11--15 mm diam. at middle, 5--10 mm diam. ca. 1 cm from apex, broadest above the middle, narrower than the pistillate portion, broader than the sterile portion; sterile staminate portion narrower than the pistillate portion, 1--1.8 cm diam.; pistils 2.9--3.9(5.7) mm long, 1.4--2 mm diam.; ovary 4--6-locular, 2 mm long, 1.4 mm diam., with sub-basal placentation; ovules 4--6 per locule, 2--3-seriate, contained within transparent ovule sac, 0.3 mm long, equal in length to funicle, style similar to style type D; style apex rounded, with style boss and with depressions surrounding stylar canal exits; style boss narrow but pronounced; stigma slightly discoid to hemispheroid, 1.6--2.2 mm diam., 0.6--1.4 mm high, covering almost entire style apex; the androecium 4--6 sided; thecae oblong, 0.3 mm wide; sterile staminate flowers 4--6-sided, 1.7 mm long, 0.9--1.6 mm wide. JUVENILE leaves more or less sagittate at base.