black-disk medick

Medicago orbicularis is native to the Mediterranean basin and the European Black Sea coast. It is known by several common names, including blackdisk medick, button clover, button medick, and round-fruited medick. This species forms a symbiotic relationship with the bacterium Sinorhizobium medicae, which contributes to nitrogen fixation in the soil. The species was first described in 1776.