Barbacenia conicostigma Goethart & Henrard

Barbacenia conicostigma Goethart & Henrard

SPECIMENS EXAMINED.—L. B. Smith and Ayensu 15982.

SURFACE VIEW.—Hairs: none present. Epidermis: cells square to rectangular on abaxial and adaxial surfaces, few rounded; thin walled. Stomata: paracytic, 21 × 15 μm; present on adaxial and abaxial surfaces.

TRANSVERSE SECTION OF LAMINA.—Isolateral; V-shaped with median abaxial sclerenchyma quite prominent below abaxial surface. Both adaxial and abaxial surfaces very slightly undulating, almost smooth. Epidermis: adaxial cells rounded to dome shaped, thin walled. Abaxial cells more rounded to rectangular, thin walled. Layer of parenchyma cells subjacent to adaxial epidermis. Cuticle: slightly thickened and ridged on adaxial and abaxial surfaces. Stomata: present on both adaxial and abaxial surfaces; small substomatal chamber present. Mesophyll: palisade tissue nonexistent. Fairly loosely arranged spongy tissue present especially toward adaxial surface; large part made up of large translucent spongy cells. Cells larger in midsection of mesophyll. Vascular bundles: 42; few commissural bundles observed. One large vessel present in each vascular bundle. Two phloem units lying laterally in flanges of Y-shaped abaxial girder. Inverted Y-shaped adaxial girder present on each vascular bundle. Bundle sheath completely surrounding each vascular bundle. Crystals and tannins: none observed.

Barbacenia conicostigma Goethart & Henrard

Barbacenia conicostigma Goethart & Henrard, Blumea, 2:341, 1937.—L. B. Smith, Contr. U.S. Nat. Herb., 35:282, 1962.—Ayensu, Smithsonian Contr. Bot., 15:63, fig. lg,h, pl. 23a,b, 46e, 1974.

TYPE.—On rocks of high peak, Serra da Lapa (Serra do Cipó), Minas Gerais, Brazil, 1824, Riedel s n (LE, holotype; B, photo 115).

DISTRIBUTION.—Brazil: Minas Gerais: Serra do Cipó, Datas, Gouvêa, Jaboticatubas.