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Phonus riphaeus, P. arborescens, P. mareoticus, P. fruticosus and Femeniasia balearica form a basal group within the Carduncellus-Carthamus-complex. The species are stenochorous. They show a pattern of geographical vicariance in SW Europe and Northern Africa. This contribution first presents new data about the distribution, phytosociology and habitat requirements of R riphaeus. Secondly, it summarizes the knowledge of all five species with the aim of outlining the ecological profile of these taxa and of applying Walter’s rule of biotope change to a supraspecific taxon. The synopsis should give an answer to the question, how the life strategy of stress tolerant perennial stayers can be successful over a macroclimatic gradient from 50 to 650 mm mean annual precipitation. The Phonus-species and Femeniasia balearica are elements in dwarf and open shrubland communities, colonizing primary habitats beyond the hygric timber line (climatic climax in deserts, pedoclimax in semi-arid and subhumid climates). The regional hydrological regime (run-off respectively run-on sites) and special local climatic conditions create a relative constancy of the environmental conditions over a broad rainfall gradient. The phenomena of convergent evolution and synvicariism become evident when comparing the life forms and the species associated with Phonus and Femeniasia. Finally, conservation aspects and the role of mobile substrates as primary habitats for apophytic species are discussed.