Philodendron squamipetiolatum Croat, Ann. Missouri Bot. Gard. 84(3):. (1997).
Appressed-climbing hemiepiphyte, occurring on understory trees in primary forest, fertile ca. 6 cm above the ground; stems trailing when juvenile, loosely appressed-climbing as adults; internodes 3–17 cm long, 6–15 mm diam., dark green, soon dark brown, drying yellow-brown, closely ridged-fissured with the surface moderately glossy, granular and with close, scalariform, tufted transversely oriented scales; cataphylls to 29 cm long, terete, unribbed, green and densely whitish scaly, promptly weathering to a loose semiorganized network of slender, pale fibers with fragments of epidermis, the fibers persisting at upper nodes, but soon completely deciduous; petioles erect to spreading, 6–16 cm long, to ca. 6 mm diam., terete, matte, dark green, surface densely covered with antrorse light green scales throughout (these ca. 6 mm long), densely granular-scurfy; blades somewhat pendent when young, spreading with petioles when mature, ovate, subcoriaceous, acuminate at apex, rounded to subcordate at base, 15–37.5 cm long, 9.5–29 cm wide (ca. 1.2–2.1 times longer than wide), (1.6–2.3 times longer than petiole), upper surface dark green, weakly glossy (subvelvety), drying dark brown, lower surface matte and much paler, drying yellow-brown; posterior lobes broadly rounded; sinus arcuate; midrib narrowly sunken and paler above, round-raised to thicker than broad, darker and densely puberulent below; basal veins 2–6(9) per side, with all free to base, or sometimes 3–5 pairs coalesced up to 1.5 cm, posterior rib sometimes lacking; primary lateral veins 5–7 per side, departing midrib at a 50–55 degree angle, weakly quilt-sunken above, round-raised to thicker than broad, darker and densely puberulent below; minor veins flat but distinct and darker than surface below, some intermittent; "cross-veins" distinct, moderately raised on drying. Inflorescences 1–2 per axil; peduncle subterete, 6-8 cm long, densely scaly; spathe 11–15.5 cm long, 2–2.5 cm diam. when furled, to 6.5 cm wide, and constricted somewhat when flattened, green outside, especially below, densely scaly (the scales whitish), deep reddish inside, especially in the tube; spadix yellowish white, 9.7–13.5 cm long, to 1.3 cm diam., only weakly constricted midway; pistillate portion 2.7–4.7 cm long in the front, 0.7–1.4 cm diam.; staminate portion 7–8.8 cm long; fertile staminate portion broadest at upper one-third and bluntly pointed at apex, 6 mm diam. 1 cm from apex; sterile staminate portion 1.2 cm diam.; pistils 2.2 mm long; ovary 5–6-locular, ca. 1.4 mm long, with axile placentation, the sides covered throughout, especially toward apex, with short pale raphide cells; locules 1–1.2 mm long; ovules 20–30 per locule, 0.1–0.2 mm long, oblong, arranged all along the length of the locules; style similar to style type B; short, 0.9–1 mm diam., drying with 2–5 depressions at apex; stigma 1–1.1 mm diam. when flattened and dried. Infructescence not seen.
Type: Panama. Coclé: Alto Calvario above El Copé, ca. 6 mi. N of El Copé, 710--800 m, 8°39'N, 80°36'W, 23 June 1994, Croat 68767 (holotype, MO-35913124; isotypes, AAU, B, CAS, CM, COL,
CR, DUKE, F, G, GH, HMNM, K, M, MEXU, NY, PMA, RSA, S, SCZ, TEX, US, VEN).
Esmeraldas: Lita, 550--650 m, 9 Jun 1978, Madison et al. 5057 (SEL); Cerro de Río Bravo de Cayapas, 250 m, 0°41'N, 78°56'W, 1 Sep 1980, HolmNielsen et al. 25535 (AAU); 40.1 km W of Lita, 350 m, 0°56'N, 78°40'W, 21 Feb 1992, Croat 72309 (L, MO, QCA, US); Lita-San Lorenzo Rd, 3.7 km W of Río Lita Bridge (below Lita), 647 m, 0°52'51"N, 78°28'30"W, 30 Jun 1998, Croat et al. 82159 (QCNE, MO). Los Ríos: La Centinela at Km 12, N of Patricia Pilar, 600 m, 16 Jul-11 Aug 1977, Dodson & Dodson 6771 (MO, SEL); Río Verde, 2 km SE of Santo Domingo de Los Colorados, 530 m, 5 Feb 1979, Dodson 7435 (SEL). Carchi: El Pailón, ca. 45 km below Maldonado, 800 m, 29 Nov 1979, Madison & Besse 7185 (SEL); Tulcán Cantón, Awá Reservation, Gualpí Chico area, 1300 m, 0°58'N, 78°16'W, 22 Jan 1988, Hoover et al. 3710 (MO, QCA). Imbabura: Lita, 812 m, 1 Sep 1982, D'Arcy 14850 (MO); Carretera Herrera-El Páramo (Santa Isabel). Estación Biológica Bilsa, 580 m, 0°21'36"N, 79°42'40"W, 18 Feb 1995, Palacios et al. 13502 (QCNE, MO). Pichincha: Reserva ENDESA, 9 km N of Km. 113 on Quito--Puerto Quito Hwy, 750--800 m, 0°5'N, 79°2'W, 28 Feb 1984, Rodríguez 247 (MO, QCA); 15 Jul 1986, Croat & Rodríguez 61483 (MO, QCA); 650--800 m, 0°3'N, 79°7'W, 11 Jun 1990, Céron & Ayala 10169 (MO); along tributary of Río Guayllabamba, 600 m, 0°10'N, 79°3'W, 7 Apr 1989, Grayum et al. 9353 (MO); vic. of Santo Domingo de Los Colorados; vicinity of Peripa, SW of Santo Doming, 250 m, 0°9'34"S, 78°28'43"W, 25 Jun 1998, Croat & Nuñez 82082 (QCNE, MO). Panama-Colombia.