Tillandsia Rauhii presents a very striking combination of colors with its green and purple leaves, white bracts, and dark violet corollas. It should prove most popular in cultivation.
Notes
Professor Werner Rauh of the University of Heidelberg has brought back to Germany a number of rare and new Bromeliads in his collections of living plants from the Andes of Peru and Ecuador. Of these, Puya argentea and Puya Rauhii have been described in "Phytologia" (vol. 5, pp.397 and 398), and now material and photographs of a giant Tillandsia have been received. The plants grow on bare vertical cliffs and must have presented quite a problem in collection. In naming this new species in honor of Professor Rauh we hope that he will solve a second problem and establish it in cultivation.
From S&D
238. Tillandsia rauhii L. B. Smith, Bromel. Soc. Bull. 8: 44, figs. 1958.
Plant flowering about 2 m high when extended.
Leaves numerous, rosulate, l-1.5 m long; blades ligulate, broadly rounded and apiculate with the apex sharply reflexed, 4-5cm wide, purple at apex, very obscurely punctulate-lepiclote.
Scape stout, decurved;
scape-bracts erect, densely irnbricate, subfoliaceous.
Inflorescence pendent, Iaxly bipinnate, glabrous;
primary bracts broadly ovate, mostly shorter than the sterile bases of the branches;
spikes linear, acute, about 7 dm long, 4 cm wide, sigmoid-curved, strongly complanate, very many-flowered.
Floral bracts densely imbricate, elliptic, obtuse, 5 cm long, ecarinate and broadly roundecl on the back, coriaceous with a narrow thin margin, finely nerved when dry. Sepals free, elliptic, obtuse, 30 mm long, the posterior ones carinate;
petals emerging between the bracts on the underside of the spike, soon flaccid and hanging straight down, 55 mm long, the blade narrowly elliptic, dark violet;
stamens exserted.
TYPE. Rauh P-379 (holotype US), on vertical cliff walls, below Florida in the valley of
the Rio Sana, 700 m alt, Piura, Peru, 1956.
DISTRIBUTION. Known from the type collection only.
Tillandsia rauhii L.B. Smith var. rauhii Rauh, J Brom Soc 41: 51-54, 79-80. 1991
Flowering plant {with erected inflorescence) up to 2.5 m tall with a short, thick, rhizome-like base.
Leaves numerous, forming a funnelform rosette 1.2 m high and 2 m wide. In cultivation all leaves are nearly erect, in nature the old leaves hang down.
Sheaths inconspicuous, to 20 cm long and 15 cm wide, concolorous with the blades,. Blades broad-lingulate, to 15 cm wide above the sheath, 1.2-1.5 m long, narrowing to a short, red-violet, recurved tip, gray-green, white waxy, only laxly lepidote.
Scape to 80 cm long, 2 cm thick, erect or slightly curved.
Scape bracts densely imbricate, the basal ones subfoliate, the upper ones smaller. Inflorescence curved, to 2 m long, laxly bipinnate with ca. 14 spreading, curved lateral spikes, to 35 cm long, 3.5-4 cm wide and 1-1.5 cm thick and a long petiolated terminal spike.
Inflorescence rachis ca. 1 cm thick, angled; internodes 3-4 cm long, glabrous, but white waxy.
Primary bracts broad-ovate, enveloping the base of the spike, shorter than the sterile part, which is 5-10 cm long, foliaged; 1 cm above the base an adaxial, bicarinate prophyll, to 5 cm long and 3.5 cm wide, waxy, violet-tipped; the upwards-following sterile bracts are also carinate.
Floral bracts fertile ones ecarinate, obtuse, to 5 cm long and 3 cm wide, distichous, densely imbricate, half overlapping; the visible part white waxy; the concealed part green, glabrous; only the upper side laxly lepidote, much longer than the sepals.
Rachis not visible, angled, flattened, excavate, glabrous, green, 1 cm across.
Flowers with a short, broad petiole, up to 10 cm long.
Sepals lanceolate, 2.8-3 cm long, 1 cm wide, obtuse, the posterior subcarinate to carinate, free, green, glabrous beneath, on the upper side laxly brown lepidote.
Petals ligulate, obtuse, 10 cm long, 1 cm wide, blue-violet, white at the base; first forming a narrow tube but soon flaccid and hanging down, drying off blackish.
Stamens and style not visible; the latter 1.5 cm longer than the anthers.
Ovary 1 cm long.
Type locality Northern Peru, in valley of Rio Sana, below the Hacienda Florida, Deptm. Lambayeque, on steep rock walls, 800m, 1956
Tillandsia rauhii has a remarkable flower-biological behaviour. The flowers on horizontally arranged spikes are located only on the underside; those on vertical spikes are located on the side that receives full sun until midday only.
The flowers are protogynous as they are in many species of the subgenus Tillandsia. Before the anthers become visible, the style with the stigma lobes exceeds the petal blades by 1.5 cm. Even in young flower buds, in which the petals are as long as the sepals, the style is longer than the still-closed anthers. In older flower buds, which are just starting to open, the anthers, the filaments, and the longer style are still folded. But then the style begins quickly to stretch and surpass the petals, the petals begin to unfold, the filaments begin to stretch. With the flower open, the filaments of the two stamen whorls have different lengths, the shorter have one basal fold while the longer are even.
Tillandsia rauhii is pollinated in nature by colibris [hummingbirds]. Capsules appear in cultivation also without cross-pollination, but rarely. After the seeds ripen the whole plant begins to die slowly, as is the case with many other big rock tillandsias. Vegetative propagation takes place before flowering with the help of the many basal adventitious offsets; postfloral offsets do not occur .
Young plants are quite different from the adults; their blades are lepidote and mostly red-violet. With age, the blades become more and more glabrous and the trichomes are replaced by a thick, white waxy layer so that all the organs except the flowers take on a white, chalky color.
Both varieties grow under the same ecological conditions, namely, on steep rock walls. Both valleys, the Sana and the Chancay, are deeply incised cross valleys of the west Andes. They receive little precipitation and bear xerophytic vegetation. The valleys are separated from each other by a 2,000-meter high plateau so that an exchange of plants by seed is difficult. In the Rio Sana valley besides Tillandsia rauhii var. rauhii, we found numerous specimens of the big T. extensa, also growing on rocks, but no other bromeliads. The Chancay valley, however, is very rich in bromeliads, especially in tillandsias. In addition to the big T. rauhii var. longispica, we found T. Iymanii Rauh, T. latifolia E. Meyen var . leucophylla (both endemic to this valley), and the very variable T. heteromorpha Mez that A. Weberbauer collected in the inner-Andean region in the valley of the Rio Pucchu (Dptm. Ancash). In addition, there were gray vrieseas such as V. cereicola (Mez) L.B. Smith and V. cylindrica L.B. Smith. At the entrance of the valley, where plant exchange is easier, grow species that are widespread in Peru: T. multiflora Benth. var. multiflora, T. latifolia E. Meyen var. divaricata (Benth.) Mez, T. juncea (Ruiz & Pavon) Poir., T. floribunda H.B.K.
All in all, the valley of the Rio Chancay is in the phytogeographical sense a very interesting valley and it seems that the famous German-Peruvian botanist A. Weberbauer did not visit it. —SeeSmith 1958dp. 44
