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Monocotyledons / Monocotiledóneas
Homalomena picturata (Linden & Andr├®) Regel
EOL Text
Homalomena picturata ranges from southwestern Costa Rica southward through Panama and Colombia to Peru, disjunct to Guyana, Surinam, and French Guiana. It occurs in moist to wet forest floor from 130--1170 m elevation. The common name is Wild dasheen (Fanshawe s. n.). The species is characterized by a combination of its usually conspicuously pubescent petioles and the reclining inflorescences. Homalomena picturata is the most widely distributed of all neotropical Homalomena species. Collections from the Guianas are especially interesting, this being the only Homalomena species in that region. Linden and André's illustration of H. picturata clearly shows plants with a white variegation along the midrib and hence the specific epithet, picturata. These markings, however, are rare and only observed on a few specimens with entirely green leaves being the more common form. Plants matching the type plant have been seen only at Guatapé in Antioquia (Grayum 7631) This collections is alive at Selby Gardens (Selby 86-850A). Homalomena picturata is a striking plant with the maroon petiole and gray-white trichomes making the species an attractive ornamental plant. Homalomena picturata is clearly the most variable species in the section Curmeria. It demonstrates a bewildering array of characters with blades varying considerably in size and ranging from nearly oblong to broadly ovate. Blade surfaces, though usually matte are sometimes glossy. Petioles though usually (sometimes merely obtusely flattened on the broadly ovate blade forms) sulcate vary from densely and conspicuously pubescent to almost glabrous. The most common leaf form is that of a narrowly ovate-elliptic blade 1.5--1.9 times longer than wide with short, bluntly pointed posterior lobes. This leaf form is prevelent throughout the range of the species and is predominant in the Guianas. It is also this leaf form which occurs in Central America. In Central America Homalomena picturata is rather rare, having been collected only in the Isthmus of Panama and near the Osa Penisula in Costa Rica. The distribution of H. picturata in Colombia is unusual since it has been collected only in the northern part of the Cordillera Central in Antioquia in areas such as Guatapé and Los Ríos. In that area two forms occur, both the common leaf form so common in Central and South America as well as a more cordate form with the whitish "fish-tail" pattern characteristic of the type of the species (as mentioned above). Since the species does occur in Central America it is curious that it has not been collected elsewhere in northern Colombia such as in the Chocó or in the lowlands of northern Antioquia adjacent to Panama. Elsewhere in Colombia H. picturata occurs only in the soutnern part of the country in the lowland Amazon basin in Amazonas Department but it should certainly be expected to be more widespread througout southern Colombia. Ecuador exhibits even more variation in leaf form than does Colombia. The common leaf form mentioned above also occurs in Ecuador though it is often more reduced in size than elsewhere in South America, often with flowering plants having blades no more than 20 cm long. In addition, blades often are more elongated in Ecuador, to as much as 5 times longer than broad (Jaramillo & Coello 3622) while still retaining the somewhat pointed posterior lobes. An unusual leaf form in Ecuador is exhibited on plants above 300 meters on the eastern slopes of the Andes ranging from Napo, Pastaza and Morona--Santiago Provinces of Ecuador to Amazonas Province of Peru. These plants have typically larger, more broadly ovate blades, and often have petioles with conspicuous trichomes which are longer and more conspicuously reddish than plant with the more common leaf forms. See for example Palacios 10107 and Croat 50346. Aside from Amazonas Department in Peru where the large ovate-cordate form of H. picturata occurs the plants collected in other areas such as Loreto, San Martín and Madre de Dios Departments have plants with the more common narrow blades with bluntly pointed posterior lobes.
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Rights holder/Author | eFloras.org Copyright © Missouri Botanical Garden |
Source | http://www.efloras.org/florataxon.aspx?flora_id=21&taxon_id=242417855 |
Internodes short, 1.5–5 cm diam; cataphylls 8–10 cm long, reddish-brown; leaves with petioles pubescent, 25–60 cm long, semiterete & sulcate, 0.5–1.5 cm in diameter, green to red-violet with grey-white trichomes; sheaths 8–11 cm long, well developed, ± auriculate and subequal at apex; blades membranaceous, cordate-ovate to oblong-lanceolate, (12)25–50(65) cm long, (5.5)12–30(42) cm wide, basal lobes subrotund to auriculate, apex acuminate, apiculate; midvein prominent; primary lateral veins 30–45 pairs; adaxial surface glabrous, medium green, occasionally with irregular white stripe along midrib; abaxial surface lighter-colored, pubescent. Inflorescences with peduncles 5.5–13 cm long, 1.5–8 cm in diameter, densely pilose, reddish-maroon; spathe 6–12 cm long, 1–2.5 cm wide at the middle, outer surface green to reddish-maroon, inner surface lighter in color, upper portion open at anthesis, apex acuminate; spadix 6–11 cm long, carpellate portion 1.9–3.5 clong, 0.7–1.1 cm in diameter, adnate adaxially to the spathe for 0.6–1.5 cm, staminate section 2.9–6 cm long, 5–9 mm in diameter at base, narrowing toward the top to 3–6 mm in diameter, cream-colored, staminodial zone 7–9 mm long, these irregular rhombic, 2–3 mm long, 1–2 mm in diameter, truncate. Carpellate flowers with ovary slightly obovoid, cream to yellow-orange, 1.4–2 mm long, 1–1.5 mm wide at the broadest point, stigma sessile, pilose, discoid, depressed in the center, 0.7–1.5 mm in diameter, slightly brownish, staminodes absent. Staminate flowers consisting of 4–5 stamens, ellipsoidal to rhombic in view from above, 1–2.3 mm long, 0.8–1.8 mm wide, distal ones smaller, connective truncate, surface irregularly rhomboidal, 1–1.6 mm long, 0.4–0.5 mm wide, 0.8–1.8 mm high, thecae lateral, roundish, ca. 0.6 mm in diameter, opening by pore, pollen ellipsoidal, inaperturate, ca. 26 µ wide, exine scabrous. Infructescences containing many berries; berries cylindrical, 4.5–5 mm long, ca. 2 mm in diameter, greenish, crested by the old stigma, many-seeded; seeds ellipsoidal, 0.6–1 mm long, 0.5–0.7 mm in diameter, testa ribbed, whitish, semitransparent.
License | http://creativecommons.org/licenses/by-nc-sa/3.0/ |
Rights holder/Author | eFloras.org Copyright © Missouri Botanical Garden |
Source | http://www.efloras.org/florataxon.aspx?flora_id=21&taxon_id=242417855 |