Black Medick

Medicago polymorpha is a plant species in the legume family Fabaceae. It is widely distributed across North America and the Atlantic islands, including the Açores and Madeira. The species was originally described by Linnaeus in 1753. Taxonomic clarification has been a subject of debate, with multiple authors proposing different typifications. Shinners (1956) suggested a typification by var. nigra, but without specimen support. Heyn (1959) later designated a specimen from Clifford as the type, while Greuter (1967) argued the name should be considered a nomen ambiguum due to an implicit typification by Krocker in 1790. Lambinon (1981) proposed the rejection of the name, but this was not accepted by the Committee for Spermatophyta in 1986. The current lectotype is based on Morison's f. 13, not the ones cited by Linnaeus or Morison himself.