Barbacenia longiflora Mart.

Barbacenia longiflora Martius

Barbacenia longiflora Martius, Nov. Gen. & Sp., 1:19, pl. 12, 1823.—Seubert in Martius, Fl. Bras., 3(1):70, 1847.—L. B. Smith, Contr. U.S. Nat. Herb., 35:282, 1962.—Ayensu, Smithsonian Contr. Bot., 15:64, fig. 24d–f, pl. 41f–h, 1974.

TYPE.—On grassy banks, Tejuco (Diamantina), Martius s n (M, holotype; F, photo 18995).

DISTRIBUTION.—Brazil: Minas Gerais: Diamantina, São João da Chapada.

Barbacenia longiflora Martius

SPECIMENS EXAMINED.—Archer 4089, Irwin 2486.

SURFACE VIEW.—Hairs: absent. Epidermis: cells rounded to rectangular, few squarish on abaxial and adaxial surfaces; walls thin. Stomata: paracytic, 18 × 15 μm; present on abaxial surface.

TRANSVERSE SECTION OF LAMINA.—Isolateral; widely V-shaped with slight median adaxial groove. Adaxial and abaxial surfaces slightly undulating. Epidermis: cells on both surfaces dome shaped, few conical; thin walled. Layer of parenchyma cells subjacent to adaxial epidermis. Cuticle: thin and ridged on adaxial and abaxial surfaces. Stomata: present on abaxial surface; substomatal chamber present; mainly flush with epidermal surface. Mesophyll: two to three layers of small cells grading into spongy tissue. Two to three layers of translucent cells present in median portion of lamina. Vascular bundles: 33; few commissural bundles observed. One to two large vessels in each vascular bundle, mostly one. Two phloem units arranged laterally in flanges of Y-shaped abaxial girder. Inverted Y-shaped adaxial girder present on each vascular bundle. Each vascular bundle completely surrounded by a bundle sheath; two to four bundle sheath cells in midportion of vascular bundles conspicuously enlarged. Crystals and tannins: none observed.