Abstract
A systematic revision of 13 species of the genus Caralluma (Apocynaceae - Asclepiadoideae - Ceropegieae) from the flora of Saudi Arabia based on the evaluation of karyological and molecular data was carried out. Karyotype criteria and polyploid variations were discussed. Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis (SDS-PAGE) and Random Amplified Polymorphic DNA (RAPD-PCR) techniques were also used in this study to distinguish these species. Karyotype features of the studied species and molecular data were used to reassess the relationships of the 13 species of Caralluma in the light of the current systems of classification.