Description from
Flora of China
Umbilicus de Candolle sect. Rosularia de Candolle, Prodr. 3: 399. 1828; Sempervivella Stapf.
Herbs perennial, usually hairy. Rootstock usually fleshy. Leaves mostly in dense, basal rosettes, usually with several rosettes per plant, alternate, sessile, flat. Flowering stems often several, arising from axils of rosette leaves (or solitary and arising from center of rosette); stem leaves alternate. Inflorescence lateral, cymose-corymbiform, paniculate-corymbiform, or spicate-paniculate, lax to dense. Flowers bisexual, 5-9-merous. Sepals connate at base. Corolla pink or white, sometimes with red or purple markings, campanulate or cupular; lobes partly connate at base, limb erect to spreading, membranous. Stamens 2 × as many as petals, inserted above corolla base, ca. 2 × as long as petals. Nectar scales cuneate to cuneate-spatulate-quadrate. Carpels erect, free, often hairy. Follicles erect, free, many seeded. Seeds striate.
Thirty-six species: C and SW Asia; three species in China.