Anthurium acutangulum
Epiphyte or rarely terrestrial; roots numerous; cataphylls subcoriaceous, 2.5-5(11) cm long, acuminate (the acumen apiculate), drying tan to light brown, persisting as linear fibers. LEAVES erect to spreading; petioles narrowly sulcate, rounded to sometimes 1 -ribbed abaxially, 3-22 cm long, 4-7 mm diam.; geniculum 1-1.5 cm long; blades elliptic to narrowly obovate, subcoriaceous, short-acuminate at apex, acute to obtuse at base, 15-34 cm long, 5-14 cm wide, broadest at middle or slightly above, both surfaces semiglossy, the lower surface punctate; midrib convexly raised above and below; primary lateral veins 8-10 per side, departing midrib at 55°-60° angle, ± straight to collective vein, loop-connected from base; collective vein rising from base, sunken on upper surface, 3-8 mm from margin. INFLORESCENCE spreading to pendent, equal to or longer than leaves; peduncle 12-61 cm long, 4-4.5 mm diam., terete or strongly ribbed abaxially, sometimes 3-ribbed adaxially, rarely 4-6 ribbed, the ribs irregularly spaced, tinged with red-violet near base, much longer than petioles; spathe green, tinged with red-violet (B & K Yellow-green 8/10), oblanceo-latc, 7-11.5 cm long, 1.2-1.5 cm wide, broadest at base, inserted at 40° angle on peduncle, sometimes slightly twisted; stipe 6-7 mm long in front, 2-3 mm long in back; spadix yellow-green (B & K Yellow-green 6/7.5), 8.5-21 cm long, 4-6 mm diam. at base, 3-4 mm diam. at apex; flowers rhombic, 4.2-6 mm long, 2.5-3.5 mm wide, the sides ± straight; ca. 5 flowers visible in the principal spiral and ca. 4-6 flowers visible in the alternate spiral; tepals glossy, weakly punctate, papillate; lateral tepals 3-3.3 mm wide, the inner margins straight and flat; pistils emergent, green; stigma brushlike with droplets, dry and brown as stamens emerge; stamens emerging rapidly from base or middle, the first lateral stamens emerging at apex as third and fourth emerge at base, exserted on transparent filaments, 0.3-0.5 mm long, 0.7-1 mm wide, retracting and holding anthers at sides of pistil, not contiguous; anthers creamy white, 0.5 mm long, 0.7-0.8 mm wide; thecae ellipsoid, divaricate; pollen white, abundant. INFRUCTESCENCE pendent; berries pale orange, ± obovoid, ca. 5 mm long. Figs. 2 and 3. The species is known from Honduras (La Mosquitia) to Panama from sea level to 1,400 m. It is found only on the Atlantic slope in Honduras and Nicaragua, but on both slopes in Costa Rica and Panama. In Panama it occurs on the Pacific slope near the Continental Divide. Anthurium acutangulum is known from welter parts of tropical moist, premontane wet, and tropical wet forest. Anthurium acutangulum is recognized by its long-petiolate, more or less elliptic, glandular-punctate leaves, which are abruptly acuminate at apex; its slender, pendulous inflorescence; its peduncle and spathe that are usually tinged red-violet, and its pale orange berries. This species is a typical member of section Porphyrochitonium despite its erroneous placement in section Leptanthurium by Engler (1905). The species is most easily confused with smaller specimens of A. ramonense but that species has a much stouter peduncle and the inflorescence is either held semierect or, if it is pendent, it is held stiffly downward and outward, not hanging loosely as in the case of A. acutangulum. In addition, the pistils of A. ramonense are not at all raised, the exposed portion being markedly squared and violet-purple. In A. acutangulum the pistils are green, appear somewhat rounded, and are promptly raised well above the tepals, giving the spadix a weakly knobby appearance.
Source : aroid.org