Plant saxicolous, pulvinate, often branched, with stout, branched, light brown roots, flowering 10-15 cm high.
Stem longer than the rosette, short to 13 cm long caulescent, to 7 cm in diameter, sometimes slightly secund.
Leaves 12-14 in number, polystichous, 3-7 cm long, the lower ones reduced and with short acuminate blades, the sheaths erect or suberect, the blades spreading or recurved, coriaceous-subsucculent, with asymmetric keel, green-grey, covered with appressed cinereous scales, looking grey, abaxially strongly nerved and looking striped, the margins with asymmetric trichomes.
Sheaths 2-3 cm long, 1-1.8 cm wide, ovate, merging imperceptibly into the blades.
Blades 1-1.5 cm wide at base, triangular, attenuate, subulate, channeled.
Scape erect, short and stout, from practically none to 1-2 cm long, nearly hidden in the rosette, imbricately concealed by few scape bracts, the lower ones foliaceous, lepidote and attenuate, the apical ones like the floral bracts, acute, red, becoming more and more glabrous.
Inflorescence terminal, simple, exceeding the rosette, 3-4 cm long, 5-8 (-10) mm wide, lanceolate acute, subterete, composed of few (2-3) distichous, sessile odorless flowers plus 1 sterile bract at the base, rhachis nearly straight, 4-angled, green, glabrous.
Floral bracts imbricate, the rhachis at anthesis not exposed, 1.6-2.5 (-2.8) cm long, exceeding the sepals, 8-10 mm wide, ovate-triangular, acute or cuspidate, submembranaceous, ecarinate, adaxially nerved, abaxially sublustrous wine-red, glabrous, the apical 4-6 mm finely grey lepidote.
Sepals 1.4-1.6 cm long, 4.5-6 mm wide, narrowly elliptic, acute, free, membranaceous, the posterior ones carinate, thickened along the keels, greenish with pink tips.
Petals 3.6-4 cm long, the blade 5 mm wide, obtuse, the margins entire not serrate, claw 3 mm wide at base, forming an erect tube with open throat, their tips spreading to strongly revolute, aster-violet, white at base.
Stamens barely included and visible, as long as the pistil, stigma 2-12 mm exserted from the throat of the corolla. Filaments 2.5-3 cm long, 0.8 mm wide, flat, thin towards the base, straight or once transversely plicate, anthers 4-5 mm long, 0.5 mm wide, linear, acute, basifixed, yellow. Pollen lime-yellow. Style 2.5-3 cm long, 1 mm wide at base and white, 0.7 mm wide at apex and yellowish, surpassing the stamens, stigma 4 mm long, 3 mm wide, lobes spreading, narrow, papillose, yellowish.
Ovary 4 mm long, 2.5 mm wide at base, ovate, light green.
Type. Bolivia. Dept. of Santa Cruz, Prov. Mendez: Paichu-Canon, between Cana Cruz and Coral Grande. July-August 1993: Len Colgan #23; (Heger #51), Coral Grande - Cana Cruz, 2700-3000 m s.m. Feb. 5 and 6; 1995 Paichu-Canon, 3000 - 3200 m s m. Ehlers EB 951002, and 2700-2900 m s m. Ehlers 951101, (holotype and paratype, WU)
Distribution: Bolivia. Dept. of Santa Cruz, Prov. Mendez: Paichu-Canon, 2700-3200 m. The plant is currently known only from the type location. It was collected for the first time in July, 1993 by Len Colgan from Australia, Ewald Heger, Wolfgang Krahn, and Helmut Alber from Germany. It was re-collected in March, 1995 by Frank Hase, Ewald Heger, Lotte Hromadnik and Renate Ehlers.
The plants grow in large clumps on the rock walls of the Paichu Canyon accompanied by Tillandsia aff. lorentziana, T. sphaerocephala, Blossfeldia sp?, and Puya sp?
Tillandsia colganii appears to be related to T. friesii Mez and T. hegeri R. Ehlers, but differs by the following characters:
From T. friesii Mez:
Inflorescence subterete, distichously arranged
Floral bracts stronger nerved and lepidote at apex,
Petals violet not red.
From T. hegeri R. Ehlers:
Plant caulescent, the rosette narrower, only to 7 cm in diameter,
Leaves shorter and more stout,
Inflorescence narrower (at most, half as wide), less complanate, subterete, composed of fewer flowers,
Floral bracts smaller and much narrower, (8-10 not 14-16 mm wide ), lepidote towards the apex, ecarinate,
Sepals shorter and only half as wide,
Petals narrower, the margins entire not serrate, the tips revolute and sometimes twisted,
Tillandsia colganii is dedicated to its discoverer Len Colgan, from Adelaide, South Australia, who discovered the plant during a trip to Bolivia in July, 1993. Mr. Colgan is the President of the South Australian Bromeliad Society and an avid bromeliad grower who, through many years of contact and cooperation, has become a good friend.
Adelaide, South Australia