Monographs Details: Habracanthus congestus Leonard
Authority: Leonard, Emery C. 1958. The Acanthaceae of Colombia, III. Contr. U. S. Natl. Herb. 31: 323-781.
Description:Latin Diagnosis - Herba vel suffrutex, caulibus subteretibus, glabris, cystolithis subpunctiformibus, lamina foliorum magna, ovata vel obovata, apice breviter acuminata, basi cuneata, integra vel undulate, aliquanto firma, utrinque conspicue pilosa, pilis ascendentibus, costa et venis lateralibus aliquanto conspicuis, cystolithis obscuris vel nullis; panicula terminalis, densa, apice subacuta, paniculae axillares minores, rhache parce hirtella, pilis ascendentibus vel patulis, rhachillis aliquanto dense hirtellis, pilis subbrunneis, septatis bracteae ramos panicularum subtendentes suborbiculares, apiculatae, sessiles, bracteae ultimae lineari-lanceolatae, subacutae, parce hirtellae; calycis segmenta lanceolate, graciliter 3-vel 5-nervata, subacuta, apice parce hirtella, pilis rigidis acutis, ascendentibus, pilis glanduliferis intermixtis, corolla rubra, parva, glabra, labio superiors erecto, lineari, apice subobtuso, curvato vel cincinnato, labio inferiors patulo, ovato, conduplicato, apice 3-lobato, lobis ovatis, rotundatis; stamina exserta, glabra; ovarium glabrum.

Description - Herbs or suffrutescent plants up to 2.5 meters high, stems subterete, glabrous, the cystoliths subpunctiform; leaf blades ovate or obovate, up to 20 cm. long and 11 cm. wide, short-acuminate at tip (?), cuneate at base, entire or undulate, moderately firm, rather densely and conspicuously pilose, the hairs ascending, about 1 mm. long, the costa and lateral veins (bout 12 pairs) moderately conspicuous, the cystoliths inconspicuous or absent; terminal panicle narrow, dense, 17 cm. long, 2 to 3 cm. broad, subacute at tip, the axillary panicles 1 or more pairs, 8 cm. long and 2 cm, broad, the rachises sparingly hirtellous, the hairs ascending or spreading, about 0.28 mm. long, the rachilla rather densely hirtellous with light brownish septets ascending hairs about 0.08 mm. long, the bracts subtending the branches of the inflorescence suborbicular and apiculate, sessile, the lowermost pair about 10 mm. long and 16 mm. wide, the others successively smaller toward the tip of the inflorescence, the ultimate bracts linear-lanceolate, 4 mm. long, 0.75 mm. wide, subacute, sparingly hirtellous, calyx segments lanceolate, 5 mm. long, 1 mm. wide at base, subacute, delicately 3- to 5-nerved, sparingly hirtellous with rigid acute ascending hairs ca. 0.1 mm. long and intermixed with these a few gland-tipped trichomes up to about 0.5 mm. long; corolla, red, about 14 mm. long, glabrous, the upper lip erect, about 8 mm. long, and 1 mm. wide, subobtuse, curled at tip, the lower lip spreading, about 10 mm. long, ovate, 3-lobed at tip, the lobes ovate, about 2 mm. long, rounded; stamens exserted 10 mm. beyond the mouth of the corolla tube, glabrous, the anthers 4 mm. long, 1 mm. thick; style slightly longer than the stamens, the stigma minute; ovary glabrous; capsules not seen.

Discussion:Characters making Habracanthus congestus easy to separate from other Colombian species are its narrow congested panicle, small red flowers, and large ovate or obovate hairy leaf blades. The specific name congestus alludes to the narrow dense panicles.