Terrestrial; stems to 25 cm long; cataphylls thin, 4.5-9 cm long, rounded at apex, weathering into coarse fibers.

LEAVES with petioles erect-spreading, 12-88 cm long, ± terete, weakly flattened or sulcate; gcniculum 1-1.5 cm long; blades ovate-triangular, moderately thick, gradually acuminate at apex, deeply lobed at base, 30-60 cm long, 19-36 cm wide; the anterior lobe 20-45 cm long; posterior lobes 14-26 cm long; sinus parabolic to hippocrepiform; both surfaces semiglossy; midrib convexly raised above and below;basal veins 5-8, the second to eighth coalesced 4.5-8 cm, prominulous above and below, yellow below, posterior rib mostly naked, weakly turned up; primary lateral veins 4-8 per side, departing midrib at 40°-45° angle, prominulous in valleys above, prominulous below; lesser veins less conspicuous; collective vein arising from the first or second basal vein, raised above and below, 3-6 mm from margin.

INFLORESCENCE spreading, shorter than leaves; peduncle 12-66 cm long, 5-7 mm diam., spathe lanceolate-triangular, green to dark violet-purple, subcoriaceous, 5-21 cm long, 2.3-8.5 cm wide, long-acuminate at apex, obtuse to rounded at base, inserted at 75° angle on peduncle; stipe 0.3-3 cm long; spadix while to greenish, yellow or purple, 7-10 cm long, 5-10 mm diam. at base, 2-5 mm diam. at apex;the flowers rhombic to 4-lobed, 1.5-3.4 cm long, 1.8-3.1 mm wide, the sides straight to jaggedly sigmoid; 5-12 flowers visible in the principal spiral, 6-16 flowers visible in the alternate spiral;tepals matte, green with purple on inner and outer edges, punctate, with sparse droplets when stamens are fresh, lateral tepals 1.5-2.2 mm wide, the inner margin convex to ± straight; pistil dark green, glossy, raised, weakly exscrtcdjust before stamens emerge; stigma narrowly elliptic, ca. 0.5 mm long, with papillae not cxserted, a small stigma droplet apparent 2-3 days before stamens emerge, dry and gray as stamens open; stamens emerging rapidly from base, or sometimes scattered throughout, exserted on short translucent filaments, 0.3-0.4 mm long, 0.6 mm wide, which retract holding stamens in a tight cluster over pistil; anthers creamy white, 0.9 mm long, 0.9-1 mm wide; thecae ellipsoid, divaricate; pollen white.

INFRUCTESCENCE with spadix to 22 cm long; berries yellow to orange, ovoid to obovoid, beaked, 1-1.5 cm long. Figs. 224 and 225.

The species is known from Costa Rica to Colombia, usually from 750 to 2,400 m elevation in premontane rain and lower montane rain forest. Some populations also occur near sea level in tropical moist forest and premontane wet forest. The species is extremely variable, especially in leaf size and shape, and spathe and spadix color. It is strange that the species has not been found in tropical wet forest or at elevations between 100 and 700 m. Perhaps further study will show that the lower elevation populations are a distinct species.

Anthurium watermaliense is an atypical member of section Pachyneurium and is not generally confused with any other species in Central America. It can be recognized by the ovate-triangular to sub-3-lobed leaf blades, the broad, frequently dark purple spathe, green to purple, stipitate spadix with long-exscrted stamens, and yellow to orange berries.

The species has long been known in horticultural circles, being first introduced from Colombia to Watermall, Belgium, by an unknown collector; although the name was validated by a short note by Bailey in the Standard Cyclopedia of Horticulture (1: 303. 1922), no type was designated. I have as yet seen no Colombian material of the species and therefore decline to name a lectotype at this time.

Map of Mesoamerican specimens with coordinates

Costa Rica Alajuela: Monteverde, 1600 m,, 22 September 1976, Kennedy & Guindon 3799 (MO)
Costa Rica Cartago: 1200-1400 m,, 1 July 1976, Thomas B. Croat 36713 (CR, K, MO, PMA).
Costa Rica Cartago: 1500 m,, 19 December 1974, Luteyn & Wilbur 4376 (MO).
Costa Rica Cartago: Tapantí Reserve, 1400-1700 m,, 7 December 1982, Gomez 19262 (MO).
Costa Rica Cartago: Dist. Santa Teresita, 1100 m, 09.57.50N 83.41.30W, 27 Jan 1992, Rivera, G. et al. 1892 (CR).
Costa Rica Costa Rica:, , Lankester 349-49 (K).
Costa Rica Heredia: 1850-1880 m, 10.12.00N 84.06.30W, 22 April 1986, Michael H. Grayum 7342 (MO).
Costa Rica Heredia: P.N. Braulio Carrillo, 1700-2000 m,, March 1983, Gomez 20220 (B, CR, K, MO, RSA).
Costa Rica Heredia: P.N. Braulio Carrillo, 700 m,, 19 April 1984, Gomez et al. 21168 (MEXU, MO).
Costa Rica Heredia: Cerro Zurqui, 1800 m, 10.03N 84.02W, Mar 1973, Stolze 1548 (F, MO).
Costa Rica Heredia: P.N. Braulio Carrillo, 1800 m, 10.11.50N 84.06.35W, 8 Nov 1986, Herrera 255 (MO).
Costa Rica Heredia: 1660 m, 10.12.30N 84.06.57W, 10 October 1992, Brad Boyle A. Boyle & H. Nelson 1174 (MO).
Costa Rica Heredia: Finca La Selva, 100 m,, , Taylor & Skotak 4529 (DUKE).
Costa Rica Heredia: Río San Rafael, 1500 m, 10.13N 84.05W, , Grayum 7021 (MBM, MO).
Costa Rica Lim—n: 280 m, 10.02N 83.25W, 6 September 1988, Michael Grayum, Gerardo Herrera & Rafael Robles 8839 (MO).
Costa Rica Lim—n: 90-200 m, 09.40.30N 83.02.00W, 31 July 1985, Michael H. Grayum & Barry Hammel 5774 (MO).
Costa Rica Lim—n: 40 m, 09.37.00N 82.39.30W, 4 Nov 1984, Michael Grayum, Willie Burton & Ernesto Salazar 4393 (MO).
Costa Rica Lim—n: 100-150 m, 09.39N 82.45W, 1 Aug 1984, Michael H. Grayum 3631 (CD, MO, RSA).
Costa Rica Lim—n: 0-50 m,, 26 February 1985, Taylor & Skotak 4435 (DUKE, MO).
Costa Rica Lim—n: Río Catarata,, 12 August 1977, Thomas B. Croat 43224 (CM, MO).
Costa Rica Lim—n: Río Sixaola, 10-50 m, 09.35N 82.53E, 12 February 1977, Burger et al. 10444 (F, MO).
Costa Rica Lim—n:, 5 November 1984, Gomez et al. 23225 (CR, MO). Costa Rica Lim—n: 3 m,, 12 February 1965, Lent 347 (MO).
Costa Rica Lim—n: 300 m,, 18 April 1985, Gomez et al. 23396 (MO, NY, US).
Costa Rica Lim—n: 800 m, 9.47.40N 83.06.30W, 10 April 1989, Gerardo Herrera 2576 (MO).
Costa Rica Lim—n: 1900 m, 9.22.45N 83.06.15W, 25 Mar. 1992, Herrera 5506 (MO).
Costa Rica Lim—n: Cordillera de Talamanca, 750 m, 09.47.40N 83.06.30W, 13 Apr 1989, Robles & Chacon 2772 (MO).
Costa Rica Lim—n: Cordillera de Talamanca, 400 m, 09.40.15N 83.03.20W, 8 Feb 1989, Herrera & Chacon 2356 (CM, CR, MO).
Costa Rica Lim—n: 300 m, 9.25.10N 83.03.00W, 25 February 1992, Reinaldo Aguilar H. Schmidt 987 (MO).
Costa Rica Lim—n: 1900 m, 09.22.45N 83.05.15W, 25 Mar 1992, Herrera, G. 5519 (INB, CR).
Costa Rica Lim—n: P.N. Cordillera de Talamanca; Cordillera de Talamanca, 1000 m, 09.24.20N 83.05.35W, 10 March 1992, Gerardo Herrera 5268 (CR).
Costa Rica Lim—n: P.N. Cordillera de Talamanca; Cordillera de Talamanca, 2000 m, 09.21.00N 83.13.20W, 13 March 1993, Gerardo Herrera 5876 (CR, MO).
Costa Rica Lim—n: P.N. Cordillera de Talamanca, 1500 m, 09.21.23N 83.13.40W, 19 Mar 1993, Fernandez, A. 734 (MO).
Costa Rica Puntarenas: 1500 m, 10.18N 84.47W, 24 July 1989, William Haber & Willow Zuchowski & Tim McDowell 9306 (MO).
Costa Rica Puntarenas: R.B. Monteverde; Cordillera de Tilarán, 1300 m, 10.16N 84.22W, 4 May 1991, Erick Bello, Eladio & Roy Cruz 2722 (CR).
Costa Rica San José: Río Para Blanca, 1600-1800 m, 10.03N 84.01W, 21 October 1975, Burger et al. 9342 (MO).
Costa Rica San José: Cerro Zurqui, 1800-2000 m,, 19 February 1978, Almeda & Nakai 3706 (MO).
Costa Rica San José:, 25 Jan. 1986, Christenson 1101 (MO).
Costa Rica San José: 600-700 m, 10.09.50N 83.57.10W, 30 August 1996, Thomas B. Croat 78766 (MO).
Panama : 1450-1480 m, 8.35N 81.50W, 6 July 1988, Thomas B. Croat 69074 (MO).
Panama Bocas del Toro: 1100-1750 m, 8.35N 81.54W, 27-31 Mar 1986, Barry Hammel & J. Trainer 14977 (MO).
Panama Bocas del Toro: less than 100 m,, , Croat & Porter 16246 (MO).
Panama Bocas del Toro: less than 100 m,, , Thomas B. Croat 38129 (CAS, F, IBE, K, MEXU, MO, NY, PMA, RSA, S, SEL, UC, US, VDB, W, WIS).
Panama Bocas del Toro:, 18 April 1968, Kirkbride & Duke 784 (MO).
Panama Bocas del Toro: 300-500 m,, 13 December 1979, António 3146 (MO)
Panama Chiriquí: 1170 m, 8.44N 81.17W, 23 June 1987, Thomas B. Croat 66697 (MO).
Panama Chiriquí: Cerro Colorado, 1200-1500 m,, 13 March 1976, Thomas B. Croat 33265 (F, MO, SEL, US, VEN).
Panama Chiriquí: Cerro Colorado, 1500 m,, 17 February 1977, Folsom & Collins 1754 (MO).
Panama Chiriquí: Cerro Colorado, 1500 m,, 17 February 1977, Folsom & Collins 1764 (MO).
Panama Chiriquí: Cerro Colorado, 1450-1750 m,, 15 Aug. 1977, Folsom et al. 4840 (MO).
Panama Chiriquí: Cerro Colorado, 1200-1500 m,, 18 August 1975, Mori & Dressler 7852 (MO).
Panama Chiriquí: Cerro Colorado, 1200-1500 m,, 18 August 1975, Mori & Dressler 7849 (MO).
Panama Chiriquí: Cerro Colorado, 1390 m,, 15 July 1976, Sullivan 359 (MO).
Panama Chiriquí: Fortuna Dam Area, 1370 m, 8.43N 82.15W, 9 April 1980, Thomas B. Croat 49898 (MO).
Panama Chiriquí: Boquete Region,, 27 May 1979, Hammel 7542 (MO). Panama Chiriquí:, 20 April 1968, Kirkbride & Duke 960 (MO).
Panama Chiriquí: 1630-1780 m, 8.46N 82.25W, 18 June 1987, Thomas B. Croat 66373 (MO).
Panama CoclŽ: 710-800 m, 89.39N 80.36W, 22 June 1988, Thomas B. Croat 68711 (CM,MO).
Panama Veraguas: Santa Fe Region, 750 m,, 3 April 1976, Croat & Folsom 33958 (CM, F, MO).
Panama Veraguas: Santa Fe Region, 700 m,, 1 December 1979, Thomas B. Croat 49035 (MO).
Panama Veraguas: Santa Fe Region, 800 m,, 5 May 1977, Folsom 2994 (MO).
Panama Veraguas: Santa Fe Region, 800 m,, 17 October 1974, Mori & Kallunki 2563 (MO).
Panama Veraguas: Santa Fe Region, 900 m,, 16 February 1974, Nee 9717 (MO,PMA).
Panama Veraguas: 480 m, 8.33N 81.08W, 28 June 1987, Thomas B. Croat 66896 (MO).

South American Specimens
Colombia Risaralda: Cordillera Central, 2500 m,, 18 Jul 1980, Idrobo et. al 9690 (U).
Ecuador :, 02 Dec 1881, Poortman 219 (P).
Ecuador : Serrania de Cutucu,, , Thomas B. Croat 75506 (MO, SEL).