Demosthenesia oppositifolia Luteyn, Brittonia 30(4): 434.  1978.  Type.  Peru.  Cuzco:  La Convención, Cordillera Vilcabamba, in dense elfin forest between Camp 6 at 3100-3300 m and summit ridges of Vilcabamba at Camp 7 at 3400-3600 m, more particularly abundant at the higher altitudes in grassland meadows and heathland vegetation, 14 Jul 1968 (fl), T. R. Dudley 11068 (holotype, NA;  isotypes, F, USM).

        "Multiple-stemmed, stiff, ascending 4-10 ft shrub" or "epiphytic shrub festooning from trees" (fide label data).  Mature stems terete, glabrous, with epidermis cracking into a reticulum exposing a dark, reddish-brown bark;  immature stems subterete, bluntly angled, densely short-white-pilose, light brown.  Leaves coriaceous, opposite, ovate to ovate-elliptic, 1.5-2.5 x 1-1.5 cm, basally broadly rounded, apically obtuse, entire, sparsely short-white-pilose on both surfaces especially along nerves and blackish- or reddish-glandular-fimbriate on both surfaces;  pinnatinerved with 2 pairs of lateral nerves, all nerves impressed above and slightly raised beneath but only the midrib and inner pair of lateral nerves conspicuous beneath;  petioles subterete, dorsally flattened, rugose, short-white-pilose, 2.5-5 x 1 mm;  pseudostipules obscure, ovate, acuminate, 1-2 mm long.  Inflorescence axillary, solitary, racemose, 8-20-flowered;  rachis subterete or bluntly 4-angled, densely short-white-pilose and sparsely glandular-fimbriate, 2-3(-5) cm long and to 1 mm in diam. at base;  floral bracts and bracteoles caducous, ovate-lanceolate, 3-4 x 1 mm, short-white-pilose;  bracteoles ciliate with glandular fimbriae;  pedicels continuous with calyx, terete, striate, densely short-white-pilose, 10 mm long at anthesis and elongating to 15-20 mm and ca. 0.5 in diam., charged with scattered reddish-brown glandular fimbriae.  Flowers with calyx densely short-white-pilose, 5-6 mm long;  hypanthium terete or slightly angled, sparsely glandular-fimbriate, 2.5-3 mm long and ca. 2-2.2 mm in diam. across the summit;  limb spreading, somewhat striate, ca. 4 mm long including the lobes;  lobes ovate, acuminate, 3.5 mm long;  sinus acute;  corolla cylindric, widening towards the apex, densely  short-white-pilose, 19-22 mm long and ca. 3-3.5 mm in diam., rust-rose, deep wine- to maroon-red (fide label data), the lobes ovate, obtuse, 2-3 mm long;  stamens 10, ca. 18 mm long;  filaments distinct, alternately ca. 1 and 2 mm long, short-white-pilose on both surfaces, not glandular-fimbriate;  anthers 16-17 mm long including tubules;  thecae granular, 3 mm long;  tubules dehiscing by clefts ca. 1-1.3 mm long;  style glabrous, 20-21 mm long.  Fruit unknown.

        Distribution.  Endemic to Peru, and known only from three collectins from the type locality.