Rhizomes: internodes short, leaves crowded at rhizome apex. Leaf blade not variegate, cordate to subreniform. Flowers: calyx tube rhombic-ovoid, conspicuously tapered above middle, 16-24 × 12-19 mm, inner surface with high reticulations, ridges 1.5-2 mm high, lobes erect or weakly spreading, 3-6 × 3-6 mm, adaxially puberulent; stamen connective extending slightly beyond pollen sacs; ovary superior; ovules 8 per locule; style notched at apex.
Flowering spring (Apr-Jun). Sandy river bluffs or ravines, deciduous forests, with Kalmia latifolia and Rhododendron maximum ; of conservation concern; 500-1000 m; N.C., S.C.
Hexastylis rhombiformis is endemic to a small area south of Asheville, North Carolina, extending south to the headwaters of the Saluda River, South Carolina. L. L. Gaddy (1986) illustrated the variation in flower shape in the species. Collections of this species made in the late 1800s were often identified as Asarum memmingeri .