Genetic differentiation and structure of Hippocrepis valentina (Leguminosae) populations

We present an analysis of isozyme variability in natural populations of the plant species Hippocrepis valentina (Leguminosae), which is endemic to the eastern Mediterranean coast of Spain and currently has endangered species status. Our results, obtained by starch-gel electrophoresis of 15 loci, sho w normal levels of variability for species with similar biology. The compar ison with the patterns of genetic variability of two closely related specie s, H. balearica and H. grosii, confirms the taxonomic status of H, valentin a as a proper species, independent of H, balearica, as previously suggested . The analysis of population subdivision shows that substantial variation a mong populations is present, and a hierarchical analysis demonstrates that when zones are defined according to their geographic location, a higher dif ferentiation among populations within zones than among zones is found, Indi rect estimates of gene flow indicate that levels of migration per generatio n are relatively low, except for a group composed of four populations, thre e of which are in close proximity. For the remaining populations, there is evidence of substantial differentiation. These results have implications fo r the design of a conservation strategy for this species.