Anthurium cymatophyllum K. Koch & Sello, in K. Koch, 1221 xi. 276. (1868). - Type: Destroyed, locality unknown, of cultivated origin said to be from Brazil (a tracing at Kew prepared by Masters from Koch's type specimen in Berlin serves as the type). Anthurium agoyanense Sodiro, Anales Univ. Centr. Ecuador 19: 286. (1905). - Type: Ecuador. Tungurahua: Agoyan waterfalls in Río Pastaza, slopes of Volcán Tungurahua, 1550 m, Sodiro s.n. (B, holotype)

Anthurium agoyanense var. eleutheroneuron Sodiro, Anales Univ. Centr. Ecuador 19:287. (1905). - Type: Ecuador. Tungurahua: slopes of Volcán Tungurahua, vic. Machay, Sodiro s.n. (B, holotype).

Anthurium rigidissimum Engl., Pflanzenr. IV. 23B (Heft 21):292. (1905). - Type: Peru. Junin: Tarma, above Huacapistana, 1900-2000 m, Weberbauer 2007 (B, holotype).

Anthurium rigidissimum var.mutatum Engl., Pflanzenr. IV. 23B (Heft 21):292. (1905). - Type: Peru. Junin: Tarma, above Huacapistana, 1900-2000 m, Weberbauer 2158 (B, holotype).

Terrestrial or epilithic, rarely epiphytic; stem 20–30 cm long, 2–6 cm diam.; roots dense (the root mass to 20 cm wide), greenish to pale reddish, greyish when dried, sometimes with raphide cells on the surface, elongate, blunt at apex, to 40 cm long, 4–10 mm diam.; cataphylls subcoriaceous, lanceolate, 5–25 cm long, narrowly rounded to bluntly acute at apex, pale green, drying brown, persisting semi-intact at upper nodes, otherwise as coarse linear fibers, sometimes with the apex remaining intact. Leaves erect to spreading; petioles (3)10–30 cm long, 5–18 mm diam., erect to spreading, D-shaped, slightly thicker than broad in juveniles and lacking the medial rib adaxially, sulcate in age with an obtuse to acute medial rib, rounded (rarely 1–2-ribbed) abaxially, the surface pale-speckled; geniculum slightly thicker and paler than petiole, 0.5–2.5 cm long; sheath 3–11 cm long, extending halfway or throughout the petiole in smaller leaves; blades subcoriaceous to thickly coriaceous, oblong-lanceolate to oblanceolate or narrowly obovate, often elliptic in smaller leaves, bluntly acute or acuminate at apex (the acumen minutely apiculate), long-attenuate to obtusely rounded or subcordate at base, (10)40–190 cm long, (2)10–35 cm wide, broadest above or near the middle, the margins flat in smaller leaves or markedly undulate especially in larger leaves; upper surface glossy to semiglossy, dark to medium green, occasionally developing a bluish, glaucous covering with age, lower surface usually semiglossy, rarely matte, concolorous or paler than upper surface; midrib above acutely raised, below obtusely ribbed at base, becoming acutely angled in upper 1/3, and then convexly rounded toward the apex, paler than surface or concolorous with it; basal veins usually present and aggregated in subcordate leaves, arcuate-ascending, free to base; primary lateral veins (7)10–20(24) per side, departing midrib at (18)40–60(70) degree angle, usually gently arcuate-ascending to within 1 cm of the margin, then abruptly ascending to the margin, convexly raised above; tertiary veins scarcely visible above, moderately to distinctly visible below, sometimes darker than surface, very weakly raised below or flat, drying raised and conspicuously visible; collective vein arising from near the base to near the apex, less prominent than primary lateral veins, sunken to weakly raised above, raised below, 2–10 mm from margin. Inflorescences erect-spreading to spreading-arching, shorter than or almost equalling leaves; peduncle (15)30–65(90) cm long, 2–11 mm diam., (2)3–7(10) times as long as petiole, pale green, sometimes tinged with red-violet, green to dark brown when dried, subterete, sometimes 1-ribbed, flexible; spathe spreading to reflexed at anthesis, recurled, subcoriaceous to coriaceous, green, sometimes tinged with red-violet, speckled with raphide cells, linear-lanceolate, 7–20 cm long, 1–3.5 cm wide, broadest near base, acute at apex, decurrent at base; spadix olive-green to grayish, becoming dark pink or maroon (B & K red-purple 2/2.5) to purplish at anthesis (B & K blue-purple 4/10), weakly to moderately tapered, rarely cylindroid, sessile to stipitate to 2.5 cm, more or less erect, rigid, held at 130–180 degree angle from peduncle, 4–28 cm long, 4–17 mm diam. near base, 3–11 mm diam. near apex, broadest near the base; flowers squarish to 4-lobed, to 3 mm long when fresh, 1.6–2.6 mm long when dried, to 2.5 mm wide when fresh, 1.4–2.2 mm wide when dried, the sides more or less straight to smoothly sigmoid; 4–14 flowers visible in principal spiral, 3–8 in alternate spiral; tepals matte; lateral tepals 1–1.6 mm wide, the inner margins tinged with pink, becoming purplish, broadly convex, the outer margins 2–4-sided; pistils scarcely emergent, green, with raphide cells; stigma oblong, slit-like, 0.4–0.6(1.0) mm long; stamens emerging irregularly from the base of the spadix in a scattered pattern, slightly exserted, lateral stamens emerging to midway, the laterals preceding the alternates by 5–18 spirals, inclined over and obscuring pistil; filaments tan, with raphide cells, exserted ca. 0.5 mm, 1–2 mm long, 0.6–0.9 mm wide; anthers pinkish, 0.6–1.1 mm long, 0.5–1 mm wide, inclined over the pistil; thecae obovoid, scarcely or not divaricate; pollen pale orange to pale yellow fading to cream, yeasty scented. Infructescence semi-erect; spathe persisting; spadix 5–27 cm long, 1.5–2.5 cm diam., with berries scattered throughout; berries violet-purple to reddish violet (B & K purple 3/10), obovoid, bluntly rounded at apex, 6–8 mm long, 5–6 mm diam.; pericarp with raphide cells; mesocarp pulpy, white; seeds 1–2 per berry, green, oblong, 3.5–8 mm long, 2.5 mm diam., with a gelatinous appendage at apex.

Type: Peru, without exact locality, Dombey s.n. (P, holotype). Anthurium cymatophyllum K. Koch & Sello, in K. Koch, 1221 xi. 276. (1868). - Type: Destroyed, locality unknown, of cultivated origin said to be from Brazil (a tracing at Kew prepared by Masters from Koch's type specimen in Berlin serves as the type). Anthurium agoyanense Sodiro, Anales Univ. Centr. Ecuador 19: 286. (1905). - Type: Ecuador. Tungurahua: Agoyan waterfalls in Río Pastaza, slopes of Volcán Tungurahua, 1550 m, Sodiro s.n. (B, holotype) Anthurium agoyanense var. eleutheroneuron Sodiro, Anales Univ. Centr. Ecuador 19:287. (1905). - Type: Ecuador. Tungurahua: slopes of Volcán Tungurahua, vic. Machay, Sodiro s.n. (B, holotype). Anthurium rigidissimum Engl., Pflanzenr. IV. 23B (Heft 21):292. (1905). - Type: Peru. Junin: Tarma, above Huacapistana, 1900--2000 m, Weberbauer 2007 (B, holotype). Anthurium rigidissimum var. mutatum Engl., Pflanzenr. IV. 23B (Heft 21):292. (1905). - Type: Peru. Junin: Tarma, above Huacapistana, 1900--2000 m, Weberbauer 2158 (B, holotype).

Tungurahua: Sodiro s.n. (B); Agoyan, Sodiro s.n. (B; photo, MO). Loja: Cerro Campana: Vilcabamba-Yangana, Km 7, 1900 m, 79°16'W, 4°17'S, 17 Jun 1979 Lojtnant & Molau 15002 (AAU, GB). Loja﷓San Lucas: 2100 m, Asplund 18056 (S); Km 25--32 Loja-San Lucas, 2200 m, Dodson & Thien 597 (MO), 659 (MO, US, WIS); 19 km N of Loja, 2070 m, 4°10'S, 79°10'W, 21 Oct 1980 Croat 50847 (AAU, B, CM, GB, K, M, MBM, MO, QCA, SEL, US). Mollococha, 10 km W of Vilcabamba, 1600 m, Harling & Andersson 21769 (GB); cultivated at Selby Gardens as 76-15-43; also Madison 2114 19 Feb 1986, Christenson 1221 (SEL); Lugma huycu 12 km N of Saraguro, 2100 m, 3°34’S, 79°15’W, 19 Jan 1989, Ellemann 66819 (AAU); Loja-Catamayo, Catamayo valley, 2000 m,, 3°57’S, 79°18’W, 25 Feb 1989, Øllgaard et al., 90743 (AAU); 2250 m, 3°54’28”S, 79°16’17”W, 20 Apr 1994, Jørgensen et al. 412 (MO). Morona﷓Santiago: Gualaquiza, Mision Bomboiza, Mision Salesiana, 700--800 m, Sparre 19272 (S). - Peru.