Scandent shrub or high-climbing liana (fide label data);  mature stems subterete to bluntly angled, smooth or striate, reddish-brown when dry, moderately short-white pilose or cinereous;  bark thin, exfoliating into log strips, dark reddish-brown;  immature twigs terete or bluntly angled, striate, densely short-white pilose or somewhat arachnoid.  Leaves coriaceous, subamplexicaul, alternate, ovate, oblong or oblong-elliptic, (4-)7-10(-12.5) x (2-)3-7.5 cm, basally rounded or subcordate, apically obtuse or bluntly acute, entire, glabrous or sparsely above, moderately to densely pilose beneath with curly white hairs, and sparsely glandular-fimbriate beneath;  pinnatinerved with 4-5 lateral veins which anastomose to form a marginal nerve, midrib and lateral nerves impressed above and raised beneath, veinlets impressed above and raised beneath but very obscure on both surfaces;  petioles subterete, dark brown, 5-7 x 2.5 mm, densely short-white pilose.  Inflorescence axillary, solitary, racemose, 10-20-flowered;  rachis bluntly angled, densely appressed white pilose, 1-7 cm long and 3 mm in basal diam.;  floral bracts ovate-lanceolate, obtuse, keeled, with prominent midrib, 3-4(-7) x 2 mm, sparsely short-white pilose, marginally glandular-fimbriate;   pedicels terete, striate, arachnoid, 5-19 mm long extending to 26 mm after anthesis and 1.5-2 mm diam.;   bracteoles similar to bracts but 2-6 mm long.  Flowers with calyx 9-11 mm long;  hypanthium barrel-shaped, 2.5-4 mm long, densely white pilose;  limb spreading, 6-7.5 mm long including the lobes, densely short-white pilose but becoming sparsely pilose towards the lobes;  lobes ovate or oblong-ovate, shortly acute, thinner at margin than in main body, 2.5-3.5 x 3.5 mm, sparsely short-white pilose externally and within;  sinuses acute;   corolla cylindric, double-layered, 6-9 x 5 mm, constricted at the throat, glabrous below becoming densely pilose distally, rosy-pink to red (fide label data), the lobes triangular acute, 1.5 mm long, very densely matted-pilose or lanate within, white;  stamens 10, ca. 6 mm long;  filaments connate (sometimes only in lower half), 2.5 mm long, with few long hairs along margins distally;  anthers 4-5 mm long including the tubules;  thecae 3 mm long, slightly granular near the base;  style 7-8 mm long.  Fruit unknown.

    Distribution.  Endemic to Peru. Rare and endandered.
 

 Key to the Varieties of Thibaudia dudleyi

1.  Pedicels 5-7 mm long;  bracteoles 2-3 mm long;  rachis 1-2 cm
     long    ..........................................................  var. dudleyi
1.  Pedicels 14-19 mm long;  bracteoles 4-6 mm long; rachis 5-7 cm
     long    ...................................................  var. pseudostellata

Thibaudia dudleyi Luteyn, Brittonia 30(4): 428, figs. 5-7.  1978 var. dudleyi.  Type.  Peru.  Cuzco:  La Convención, Cordillera Vilcabamba, in reduced open elfin forest (very wet) along the top of a ridge (ceja), around clearings at Camp 4 and extending down to Camp 3, 2300-2660 m, Dudley 10750 (holotype, NA;  isotype, USM).  Image:  SEM of pollen.

Thibaudia dudleyi Luteyn var. pseudostellata Luteyn, Brittonia 30(4): 430, figs. 8, 12-14.  1978.  Type.  Peru.  La Mar:  Ayacucho, finger of elfin forest extending into puna near Cusimachay, ca. 25 km NE of Tambo, San Miguel, Ayna and Hda. Luisiana, in dense and isolated 40-50 ft elfin hepatic forest at timberline, Punccu camp, 3220 m, Dudley 12065 (holotype, NA;  isotype, USM).  Images:  Line-drawing.  SEM of stellate hairs.  SEM of broken hair.