Published online by Cambridge University Press: 24 February 2014
A synopsis of the native and naturalised species of Senna (Leguminosae: Caesalpinioideae) in the Arabian Peninsula is provided. Nine species are recognised. A key to the species is presented. For each species the accepted name with selected synonymy is given, followed by a diagnostic morphological description, the geographical distribution, details of habitat preference, and citation of specimens studied. Preliminary regional conservation assessments are given for all species.