Cullen is a genus of flowering plants in the legume family, Fabaceae, placed in the order Fabales. It was established by the German botanist Friedrich Kasimir Medikus in 1787, with Cullen corylifolium as its type species. The genus was formerly submerged within broader circumscriptions of the closely allied genus Psoralea, and several older names — Bauerella, Baueropsis, and Meladenia — are now treated as synonyms of Cullen.
Species of Cullen are native to tropical, subtropical, and arid regions of Africa, Asia, and Australia. Notably, despite what its species epithet might suggest, Cullen americanum is not native to the Americas. As of April 2023, Plants of the World Online recognized 34 accepted species in the genus (GBIF's own taxonomic backbone lists 43 descendant taxa, a figure that likely includes synonyms and infraspecific names alongside accepted species).
Among the recognized species are Cullen americanum, Cullen cinereum, and Cullen corylifolium — the latter serving as the genus's type species. The genus sits within the tribe Psoraleeae of the subfamily Faboideae (Fabaceae), reflecting its taxonomic kinship with Psoralea and other legumes historically grouped alongside it.
Distribution
Cullen species occur across tropical, subtropical, and arid regions of Africa, Asia, and Australia. Cullen americanum is not native to the Americas despite its epithet.
Taxonomy Notes
Cullen was erected by Medikus in 1787 and was formerly included within broader definitions of the allied genus Psoralea; Bauerella, Baueropsis, and Meladenia are treated as synonyms. Its type species is Cullen corylifolium. GBIF places the genus in family Fabaceae, order Fabales.
