Umbilicus is a genus of over ninety species of flowering plants in the family Crassulaceae. Many of its species have been given synonyms under different genera such as Rosularia, Cotyledon, and Chiastophyllum. However, those that remain in Umbilicus are listed below:Umbilicus chloranthus Umbilicus chrysanthus Umbilicus erectus Umbilicus horizontalis Umbilicus intermedius Umbilicus oppositifolius Umbilicus rupestris Other (unnamed) species

Sempervivoideae is the largest of three subfamilies in the Saxifragales family Crassulaceae, with about 20–30 genera with succulent leaves. Unlike the two smaller subfamilies, it is distributed in temperate climates. The largest genus in this subfamily is Sedum, with about 470 species.