Diffuse herb, 0-1 m tall. Stem erect or ascending, subhexagonal, glabrous or upper portion puberulous. Petiole 0.5-5 cm long, glabrous or margins of channel puberulous; blade thin, ovate to oblong, 5.5-14 x 2-4 cm, entire or undulate, slenderly acuminate (tip itself mucronulate), narrowed at base, both surfaces glabrous, cystoliths prominent and numerous under a lens; primary vein and secondary veins (4-6 pairs) rather obscure, puberulous. Cymes 3-parted, usually several in each axil; peduncle 2 mm long from base to fork, 5-9 mm long from fork to base of cymule bracts, hexagonal, flattened toward tip, angles acute, puberulous; bracts produced at fork of cyme subulate, 3.5 x 0.5 mm wide at base; cymule bracts ovate to suborbiculate, cuspidate-mucronulate at apex, cuneate at base, prominently 3- to 5-veined, sparingly puberulous, especially veins, margin ciliate with trichomes of 0.75-1 mm long, upper bract 12 x 10 mm, lower 10 x 7.5 mm; bracteoles lanceolate, 4 x 1.25 mm, aristate at apex, hirtellous except glabrous at base. Calyx 3 mm long, puberulous or glabrous near base, pubescence a mixture of ascending and shorter gland-tipped trichomes, lobes narrowly triangular, 2.5 x 0.5 mm wide at base; corolla violet or mauve, 15 mm long, finely and rather densely pilosulous except basal portion, tube erect, 1.25 mm wide at base, 2 mm wide apically, upper lip narrowly ovate, 8 x 4 mm, subobtuse, lower lip slightly longer and narrower than upper, 3-lobed at tip, lobes 0.75 x 0.5 mm, rounded; stamens exserted 7 mm beyond mouth of corolla tube, filaments flattened, retrorsely and sparingly pilosulous towards base, anther thecae superposed, 1 x 0.5 mm. Capsule ovoid, flattened, 6 x 3-4 x 1 mm, densely and retrorsely pilosulous, retinacula 1 mm long, obliquely cucullate and acute; seeds suborbicular, flattened, 1.75 mm in diameter, 0.5 mm thick, dark brown, retrorsely aculeate.
Guianas present, Southern America: Brazil North (Amapá present, Pará present); Brazil Northeast (Bahia present, Ceará present, Pernambuco present)
Guianas and Brazil (Amapá, Pará, Ceará, Pernambuco, Bahia); 20 collections studied (GU: 1; SU: 1; FG: 5).