Anthurium santiagoense Croat, Ann. Missouri Bot. Gard. 78(3): 718. (1991).
Description based on dried material only. Terrestrial; stem 1.5–2 cm diam.; roots few, pale grayish, pubescent, elongate, to 4 mm diam.; cataphylls probably coriaceous, 10–13.5 cm long, acute at apex, yellow-green, persisting as fine, pale, linear fibers; petioles 24.5–27 cm long, 1–1.2 mm diam., triangular, flattened to broadly sulcate adaxially, the margins acute, acutely angled abaxially; blades subcoriaceous, more or less broadly elliptic to oblong-elliptic, abruptly acuminate to long-acuminate at apex (the acumen 15–20 mm long), narrowly acute at base, 75–97 cm long, 21.5–29 cm wide, broadest just above the middle, matte to weakly glossy, greenish; midrib prominently raised above, higher than broad and paler than surface below; primary lateral veins 25–33 per side, departing midrib at 60–75 degree angle, straight-ascending to the collective vein, slightly raised above and below, slightly paler than surface below; interprimary veins almost as conspicuous as primary lateral veins, drying raised above and below; tertiary veins visible when dried, raised; collective vein arising from near the base, drying raised above and below, equally as prominent as primary lateral veins, 7–20 mm from margin. Inflorescences with peduncle 20–48 cm long, 5–11 mm diam., drying greenish; spathe reflexed, subcoriaceous, green, broadly lanceolate, 7–8 cm long, 1.8–2.6 cm wide, broadest near the base, abruptly acuminate at apex, 4 mm long; stipe 7–17 mm long in front, 1–3 mm long in back; spadix deep purple, cylindroid, erect, sometimes slightly curved, 6.5–7 cm long, 5–6 mm diam. midway; flowers more or less square, 1.5–2.1 mm in both directions; 7–10 flowers visible in principal spiral, 6–7 in alternate spiral; lateral tepals 0.9–1.2 mm wide, the inner margins more or less straight, the outer margins 2-sided; pistils somewhat exserted; stigma ellipsoid, 0.3 mm long, droplets drying as abundant crystals and persisting; stamens emerging well above tepals; filaments translucent, flattened, 0.7 mm wide; anthers yellow, 0.4–0.5 mm lon, 0.6 mm wide; thecae oblong, 0.2–0.3 mm wide, slightly divaricate; pollen fading to tan. Infructescence not seen.
Type: Ecuador. MoronaSantiago: Proveduria, confluence of Río Bomboiza and Río Zamora, 600 m, 3°25'S, 78°27'W, Palacios 1492 (MO 3420759 holotype, NY, QAME, isotypes).
MoronaSantiago: Río Bomboiza and Río Zamora confluence, Proveduria, 600 m, 3°25'S, 78°27'W, Palacios 1492 (MO, NY, QAME); Cordillera de Cutucú, W slopes: LogronoYaupi, 2°46'S, 78°6'W, Madison et al. 3382 (SEL). Zamora-Chinchipe: 900 m, 4°07'S, 78°37'W, 18 Oct 1991, W. Palacios, G. Aymard & E. Freire 8307 (MO, US); 1600--1800 m, 4°07'S, 78°34'W, 05 Dec 1990, W. Palacios & D. Neill 6527 (MO).
Description based on dried material only.