Rhizomatous and stoloniferous perennial. Flowering stems stout, erect, glabrous or sparsely minutely papillate, 30-90 cm tall. Lvs ovate to narrowly elliptic, tapering to short petiole, becoming sessile above, prominently 3-veined, acute, glabrous or upper lvs scabrid on margins, 4-10 × 1.5-3 cm. Infl. a dense terminal cyme with lower branches bearing few-flowered dichasia; bracts linear-lanceolate, scabrid on margins, 1-2 cm long. Pedicels 3-5 mm long. Calyx cylindric or slightly inflated, (15)-18-23 mm long, glabrous or hairy; teeth broadly triangular, acute. Petals pink; claw > calyx; limb spreading, entire or emarginate, c. 1 cm long; coronal scales paired at base of limb, small, triangular. Capsule = calyx, oblong-ovoid, but often not formed; carpophore 2-3 mm long. Seeds blackish, c. 1.8 mm long.