Gen. N. Amer. Pl. 1: 157. 1818.
Herbs or subshrubs, perennial, synoecious. Rhizomes somewhat woody, white to beige or blue (then drying blackish), cortex corky or papery, loose exfoliating. Leaves: petiole short or absent. Inflorescences terminal, paniclelike or corymblike thyrses; cymules 3–5-flowered; prophyllar bracteole subtending each flower persistent. Pedicels present. Flowers bisexual, campanulate; hypanthium adnate to ovary proximally, free distally, funnel-shaped; petals (4–)5(–7), white, yellowing with age, ovate or oblong to lanceolate, reflexed upon maturation; nectary lining hypanthium, lobes small, alternating with filaments; styles filiform; stigmas capitate. Pseudodrupes usually multiple, petals persistent, forming neck at apex; exocarp leathery.
North America, n Mexico, s Europe (Balkan peninsula), temperate regions.
Circumscription of species within Comandra has varied, as have opinions about whether Geocaulon is distinct. C. L. Hitchcock and A. Cronquist (1973) considered Geocaulon as a species of Comandra, whereas M. L. Fernald (1950) recognized separate genera. The treatment here follows the most comprehensive study of Comandra to date (M. A. Piehl 1965), which recognized a single variable species with four subspecies.