Juncus ramboi subsp. colombianus Balslev

  • Authority

    Balslev, Henrik. 1996. Juncaceae. Fl. Neotrop. Monogr. 68: 1-167. (Published by NYBG Press)

  • Family

    Juncaceae

  • Scientific Name

    Juncus ramboi subsp. colombianus Balslev

  • Type

    Type. Colombia. Cundinamarca: Macizo de Bogotá, Quebrada de las Delicias, 2650-2770 m, 11 Jul 1939, Cuatrecasas 5437 (holotype, COL!; isotypes, F!, US!).

  • Description

    Subspecies Description - Perennial, densely cespitose herbs, 20-30(-65) cm high. Rhizome creeping, ca. 2 mm diam., densely branching, covered with stramineous or brown scales to 5 mm long, internodes short and the culms arising densely crowded. Culms erect, 0.6-1.2 mm diam., equally thick from base to top, with 12-18 longitudinal ridges, pith continuous, parenchymatous. Foliar leaves absent. Cataphylls 3-4 to each culm, the uppermost and longest one to 4.5 cm long with an up to 4 mm long, acicular, rudimentary blade, castaneous. Inflorescence pseudolateral, capitulate, 10-20-flowered, composed of 2-4 densely crowded cymes. Lower inflorescence bract appearing as a continuation of the culm, 2-5(-9) cm long, round in x.s., distal bracts obtuse, scariose, ca. 1 mm long. Each flower clasped by two 1.5-2 mm long, obtuse, castaneous or scariose bracteoles. Tepals subequal, lanceolate, acute, castaneous, often pale green along the midrib, turning stramineous, outer tepals 3.5-4.5 mm long, concave, inner tepals slightly smaller and flat or slightly concave. Stamens 6, 1.6-2 mm long; filamente flat, widened at the base; anthers linear, 0.5-0.8 mm long. Capsule ovoid to obovoid, round to trigonous in x.s., 2.5-3.5 x 1.5-2.2 mm, castaneous, sometimes pale brown at the base, 3-septate. Seeds ellipsoid or curved, apiculate, 0.5-0.6 x 0.2-0.3 mm, reticulate by longitudinal ridges and transverse lines, castaneous below a hyaline outer seed coat.

  • Discussion

    Juncus ramboi is peculiar in having a parenchymatous dense pith and not an aerenchymatous pith of asteriform cells, as is common in Juncus subgen. Juncus. The wiry thin culms and the rigid, castaneous flowers are also very distinct. The typical variety is known from a few collections from Rio Grande do Sul and Santa Catarina in SE Brazil (outside of the range of this monograph), where it grows in bogs, pastures, dry woods, and brook banks at elevations of 900-1600 m.

    In the department of Boyaca, J. ramboi subsp, colombianus is used for making baskets and souvenirs (Torres R. 3312A, COL).

    Distribution and Ecology: Juncus ramboi subsp, colombianus is distributed in the E cordillera of the Andes in Colombia in the departments of Boyacá and Cundinamarca. It grows in páramos at elevations of 2650-3200 m, on moss-covered damp soil along gorges (Langenheim 3644) or in water on open plateaus (Galen Smith 1373).

  • Common Names

    esparto

  • Distribution

    Colombia South America| Boyacá Colombia South America| Cundinamarca Colombia South America|