Cavendishia megabracteata Luteyn, Brittonia 28: 49.  1976.  Type.  Panama.  Chiriquí: Ridge E of Cerro Horqueta, 1700-1900 m, 4 Jan 1974 (fl), Luteyn & Wilbur 4594 (holotype: DUKE, photo NY;  isotypes: E, F, GH, LL, MICH, MO, NY, PMA, UC, US).

        Terrestrial or epiphytic shrub to 2.5 m tall;  stem base to 5 cm in diam.;  mature branches terete, minutely striate, glabrous;  bark brown when fresh, but drying grayish- to reddish-brown;  twigs terete to bluntly angled, striate, glabrous, reddish-brown.  Leaves ovate, lanceolate, lance-elliptic, elliptic, or oblong, (4-)6.5-12(-15) x (1-)2.5-7 cm, basally obtuse, rounded, truncate or cuneate-attenuate, apically acuminate and often abruptly so, often puberulous at base of midrib and lateral nerves on upper surface;  5-7-plinerved, midrib inconspicuously raised and thickened through proximal 1 cm, otherwise weakly impressed above, inner pair of lateral nerves moderately or weakly impressed above but sometimes plane or raised distally, outer lateral nerves and veinlets raised and usually very conspicuous above rarely impressed, all nerves raised beneath but veinlets often obscure;  petioles subterete, often flattened adaxially, rugose, rarely striate, 4-10(-14) mm long and 1-2.5(-3) mm in diam., glabrous to densely puberulent adaxially when young often glabrate.  Inflorescence (2-)5-10(-14)-flowered (often lowest one or two nodes sterile), obconic to spherical in bud;  rachis coarsely and bluntly angled, striate, glabrous, (0.6-)0.8-3.5(-6) cm long and 1.5-2 mm in diam., cream-colored and often suffused with pink when fresh, rarely with a few clavate glands or cartilaginous teeth at base (in var. megabracteata);  floral bracts translucent when dry, smooth, oblong, obovate, or rarely subrotund, (2-)3-6(-7) x (1-)1.5-2.5(-4.5) cm, basally narrowed and somewhat clasping, apically rounded, usually deeply emarginate, with minute, red, clavate, glandular fimbriae abaxially, pale purplish, bright rose, lavender-pink, or dark pink when fresh;  pedicels swollen distally, striate, glabrous, (8-)10-16(-19) mm long and (0.5-)1(-1.5) mm in diam., cream-colored, often suffused with pink or red when fresh, rarely weakly glandular at distal end;  bracteoles with or without prominent midrib, ovate, lanceolate, lance-elliptic, or nearly linear, 1.5-2(-5) x 0.5-1.5(-4) mm, apically glandular-callose.  Flowers:  calyx glabrous, 4-11(-13) m long, cream-colored, often suffused with pink or red when fresh;  hypanthium cylindric, ribbed, 1.5-5 mm long and 3-5 mm in diam. across base, basally apophysate and deeply lobed with lobes straight to flaring outward and extending to or well below articulation;  limb cylindric to slightly spreading or campanulate, smooth or ribbed, minutely papillate, (2.5-)3-7.5(-9) mm long;  lobes triangular, (1-)1.5-2(-2.5) mm long, erect after anthesis, tips completely glandular-callose or callose apically, centrally, or only marginally;  sinuses subacute when fresh, but drying obtuse to broadly rounded, rarely flat;  corolla slightly constricted basally and at throat, often translucent when dry, 17-40(-43) mm long and 6-9 mm in diam., glabrous or rarely pilose distally, tube dull or glossy white, often basally pink to pinkish below grading through violet to pale purple above (in var. megabracteata), limb white, lobes oblong, obtuse, 1.5-2 mm long, reflexed at anthesis, white sometimes marginally purple (in var. megabracteata);  stamens 16-36 mm long;  filaments densely puberulous distally, alternately 2.5-7.5 mm and 6-13.5 mm long;  anthers alternately 15-32.5 mm and 12-26.5 mm long;  thecae 4.5-13 mm long;  style 18-41 mm long.  Mature berry not seen.

        Distribution (Map).  Endemic to Panama, where it is found in western Chiriquí and Coclé Provs., at elevations of 1700-2500 m and 600-900 m, respectively.
     

     Key to Varieties of Cavendishia megabracteata

    1.   Leaf base obtuse, rounded, or truncate; inflorescence
         (2-)5-9(-12)-flowered; rachis (0.6-)0.8-2(-3.5) cm long and ca. 2
         mm diam.; floral bracts (20-)30-60(-70) mm long; calyx 7-11(-13)
         mm long; corolla 31-40(43) mm long; western Chiriquí Prov. at
         1700-2500 m elev. .......................................... var. megabracteata
    1.  Leaf base cuneate-attenuate; inflorescence ca. 10-14-flowered;
         rachis 3.5-6 cm long and 1.5-1.7 mm diam.; floral bracts 30-35 mm
         long; calyx 4-5.5 mm long; corolla 17-20 mm long; Coclé Prov. at
         600-900 m elev. ...................................................... var. attenuata

    Cavendishia megabracteata Luteyn var. megabracteata.  Images:  Habit. Flowers.

        Leaves ovate, lanceolate, lance-elliptic, or oblong, (4-)8-12(-15) cm long, basally obtuse, rounded, or truncate.  Inflorescence (2-)5-9(-2)-flowered;  rachis (0.6-)0.8-2(-3.5) cm long and ca. 2 mm diam.;  floral bracts (20-)30-60(-70) x (10-)15-25(-45) mm, pale purplish, bright rose, or dark pink when fresh.  Calyx 7-11(-13) mm long;  hypanthium 2-5 mm long, the apophysate base straight or flaring, extending well below articulation;  limb cylindric to slightly spreading, smooth, (4-)5-7.5(-9) mm long;  corolla 31-40(-43) mm long;  stamens 24.5-36 mm long;  filaments alternately 2.5-7.5 mm and 7.5-13.5 mm long;  anthers alternately 21.5-32.5 mm and 16-26.5 mm long;  thecae 6-13 mm long;  style 32-41 mm long.

        Distribution (Map).  Slopes of Volcán Barú and Cerro Horqueta, western Chiriquí Prov. (Panama), in montane cloud forest or along shaded trails through forest, at elevations of 1700-2500 m.
     

    Cavendishia megabracteata Luteyn var. attenuata Luteyn, Fl. Neotrop. Monogr. 35:  254.  1983.  Type.  Panama.  Coclé: 8 km above El Copé nr. continental divide, 600 m, 10 Jan 1978 (fl), Hammel 823 (holotype: MO, photo NY neg. 10870; isotype: DUKE).

        Leaves lance-elliptic to broadly elliptic, 6.5-10.5 cm long, basally cuneate-attenuate.  Inflorescence 10-14-flowered;  rachis 3.5-6 cm long and 1.5-1.7 mm diam.;  floral bracts 30-35 x 15-26 mm, purple, pink to lavender-pink when fresh.  Calyx 4-5.5 mm long;  hypanthium 1.5-2.5 mm long, the apophysate base straight, extending to articulation;  limb campanulate, ribbed, 2.5-3 mm long;  corolla 17-20 mm long;  stamens 16 mm long;  filaments alternately 3 mm and 6 mm long;  anthers alternately 15 mm and 12 mm long;  thecae 4.5-5 mm long;  style ca. 18-20 mm long.

        Distribution (Map).  Known only from the type locality in Coclé Prov. (Panama), where it is found in very wet and windy cloud forest, at elevations of 600-900 m.  This variety should be considered  Rare and endangered.