A phylogenetic and karyological analysis of the small and poorly known genus Cerinthe L. (Boraginaceae-
Lithospermeae) was performed using ITS sequences and standard chromosomal techniques. All taxa are
diploid with 2n = 16 or 2n = 18 and show a variable degree of infraspecific variation, in particular in the
polymorphic C. major and C. minor. Change in base number is associated with an early split between the
two well-supported clades of C. major, corresponding to Cerinthe sect. Cerinthe, and that of all other taxa
belonging to C. sect. Ceranthe, with the base x = 8 found only in the strictly annual C. major group, and
x = 9 in the other five species of the genus: C. minor, C. glabra, C. tenuiflora, C. retorta and C. palaestina.
The latter section is subdivided into the E Mediterranean, annual lineage of C. palaestina–C. retorta and
the mainly continental, perennial group of C. minor–C. glabra, the sister of which is the Corsican endemic
C. tenuiflora. The hypothesis that x = 9 represents the primary haploid number and x = 8 is derived through
descending aneuploidy, is discussed. A taxonomic revision of the genus is provided and the following formal
taxonomic changes are proposed: C. major L. subsp. oranensis (Batt.) Selvi & Cecchi, stat. nov.; C. major
L. subsp. purpurascens (Boiss.) Selvi & Cecchi, stat. nov.; C. minor L. subsp. cleiostoma (Boiss. & Sprun.)
Selvi & Cecchi, stat. nov. Cerinthe tenuiflora, C. retorta and the poorly known C. palaestina are well-defined
species with little internal variation.