Small shrub; stems subquadrangular (the angles rounded), minutely strigose, the hairs averaging 0.13 mm. in length, more or less bifari- ously arranged on the lower portion of the stem, those of the upper part of the stem golden-brown; leaf blades oblong-elliptical or obo- vate, up to 21 cm. long and 9 cm. wide, subobtuse and apiculate, narrowed at base and decurrent on the petiole, rather firm, entire or undulate, the upper surface glabrous except costa and lateral veins, these minutely strigose, the hairs similar to those of the stems, the cystoliths prominent, the lower surface glabrous except the costa and lateral veins (10 to 12 pairs) these densely but minutely strigose, the hairs golden-brown, up to 0.32 mm. long, those of the costa confined chiefly to its margins, the cystoliths conspicuous, 0.25 to 0.32 mm. long; petioles up to 3.5 cm. long, rather stout, minutely strigose like the stems; flowers secund, borne in a terminal panicle about 16 cm. long and broad, the lateral branches of the inflorescence composed of 1 to 3 rather loose spikes, these few-flowered, up to about 3 cm. long, the peduncle 2 mm. long, the lowermost internodes of the panicle 2 cm. in length, the others successively shorter towards the tip of the inflorescence, all of the internodes minutely and densely golden-brown strigose, the hairs averaging 0.2 mm. in length, more or less bifariously arranged, the pedicels up to 2 mm. long, glabrous or nearly so, the lowermost branches of the inflorescence subtended by small leaves, the other branches by lanceolate bracts, these up to 5 mm. long and 1.25 mm. wide, acute, firm, strigose with minute golden-brown hairs; bractlets resembling the bracts; calyx 7 mm. long, deeply segmented, the segments lanceolate, 3.5 mm. wide at about the middle, acute, firm, 3-nerved, strigose or puberulous, the hairs curved, averaging 0.13 mm. in length, golden-brown; corollas purple, up to 6.5 cm. long, sparingly and minutely pubescent, the hairs spreading, up to 0.2 mm. long, gland-tipped, the corolla tube subcylindric, about 2.5 mm. broad at base, 5 mm. broad at mouth, the upper lip erect, linear-oblong, 3.3 cm. long, about 6 mm. wide near base, 3 mm. wide near the rounded shallowly emarginate tip, the lower lip more or less spreading, oblong, 3.5 cm. long, 1 cm. wide, truncate and shal- lowly 3-lobed at tip, the lobes rounded or obtuse, 2.5 mm. wide and 1 mm. long; stamens glabrous, exserted 2.5 cm. beyond the mouth of the corolla tube, the anther lobes superposed one about 0.5 mm.  above the other, the upper lobe horizontally attached, the lower more or less vertical and terminated at base by a white blunt spur 0.5 mm. long; style slightly shorter than the stamens; ovary glabrous; capsules not seen.
Type in the U. S. National Herbarium, No. 1798544, collected in wet woods between Quebrada de la Hormiga and San Antonio del Güamués, Comisaría of Putumayo, Colombia, 330 meters altitude, December 18, 1940, by J. Cuatrecasas (No. 11157).
Justicia pelianthia is readily recognized by its large erect purplish corollas, by the flowers being secund in short spikes, these forming a broad, rather flat panicle, and by the minute golden-brown pubescence of the panicle branches. Apparently it has no close relatives among the Colombian species. The specific epithet is from the Greek πελιός, livid, and ἄνθειον, blossom.