Justicia mcdowellii

Primary tabs

Justicia mcdowellii


Herb to 1.2 m tall. Stem ascending, quadrangular, pilose, trichomes sordid to yellowish. Petiole short or lacking, if present, then 5 mm long, sparingly pilose; blade thin and membranous, elliptic to oblong to narrowly ovate, 15-25 x 6-11 cm, entire or slightly undulate, short-acuminate at apex, attenuate at base, upper surface dark green when dry, lower surface a lighter yellow-green when dry, both surfaces sericeous, espeically on venation; primary and secondary veins (6-7 pairs) rather obscure above, more prominent on lower surface. Inflorescence terminal, long-pedunculate spikes, these usually paired, 8-15 cm long; peduncle subquadrangular, 7-16 cm long, pilose and puberulous; rachis subquadrangular, pilose and puberulous; bracts greenheteromorphic, larger bract obovate to suborbicular, 8-9 x 7-8 mm, rounded and apiculate at apex, abruptly narrowed and cuneate at base, thin, primary and secondary veins prominent, both surfaces gland-dotted, pubescent along primary vein, margin ciliate, sterile bract greatly reduced, linear, 6-7 x 0.4-0.6 mm; bracteoles linear, 6 x 0.5 mm, long-aristate at apex, puberulous, margin ciliolate. Flowers sessile to subsessile; calyx 5-lobed, 5.5-6 mm long, lobes equal, linear-lanceolate, 5-5.5 x 0.5 mm, aristate at apex, glabrous, margin ciliolate; corolla white, 22-22.5 mm long, puberulous and gland-dotted, tube narrowly cylindrical, 19-19.5 mm long, 2 mm in diam. at base, enlarged to 3 mm at 2.5 mm above base, then slightly constricted, 2.5 mm wide at mouth, limb short, upper lip erect, narrowly ovate, 5 x 1.75-2 mm, 2-lobed, lobes 0.5 x 0.5 mm, lower lips spreading, 4 mm long, lobes 2 mm long, all narrowly ovate and apically rounded; stamens exserted 4 mm beyond mouth of corolla tube, anther thecae superposed, subequal, vertically attached to connective, lower theca inconspcisouly apiculate, filament flattened; pistil ± equaling stamens, style glabrous, stigma 2-lobed, minute, rounded. Capsule clavate, 15 x 4 x 3 mm, puberulous; seeds dark reddish brown, lenticular to subspheric, 3 x 2 1 mm, surface and margin covered with knoblike papillae.


Guyana endemic
Endemic to Guyana, known only from the type locality, mixed forest, with palms, Heliconia, Marantaceae, and Gesneriaceae in understory.


Flowering and fruiting in .