Lunularia

Lunularia cruciata, the crescent-cup liverwort, is a liverwort of order Marchantiales, and the only species in the genus Lunularia and family Lunulariaceae. The name, from Latin luna, moon, refers to the moon-shaped gemmacups.

Lunularia occurs commonly in western Europe, where it is native to the region around the Mediterranean. It is also common in California, where it now grows "wild", and is known as an introduced weed in gardens and greenhouses in Australia. In America, the species grows only as a sterile form, easily recognized by the crescent-shaped cups containing asexual gemmae.