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Heterostyly is a floral polymorphism characterized by the reciprocal position of stamens and stigmas in different flower morphs in a population. This reciprocal herkogamy is usually associated with an incompatibility system that prevents selfing and intra-morph fertilization, termed a heteromorphic incompatibility system. In different evolutionary models explaining heterostyly, it has been alternately argued that heteromorphic incompatibility either preceded or followed the evolution of reciprocal herkogamy. In some models, reciprocal herkogamy and incompatibility have been hypothesized to be linked together during the evolution of the heterostylous system.We examine the incompatibility systems in species with different stylar polymorphisms from the genera Lithodora and Glandora (Boraginaceae). We then test whether evolution towards reciprocal herkogamy is associated with the acquisition of incompatibility. To this end, a phylogeny of these genera and related species is reconstructed and the morphological and reproductive changes that occurred during the course of evolution are assessed.Both self-compatibility and self-incompatibility are found within the studied genera, along with different degrees of intra-morph compatibility. We report for the first time extensive variability among members of the genus Glandora and related species in terms of the presence or absence of intraspecies polymorphism and heteromorphic incompatibility. Overall, our results do not support a tight link between floral polymorphism and incompatibility systems.The independent evolution of stylar polymorphism and incompatibility appears to have occurred in this group of plants. This refutes the canonical view that there is strong linkage between these reproductive traits.

LUQUE, T. & VALDES, B., 1984. Karyological studies on Spanish Boraginaceae: Lithospenum L. sensu lato. All of the Spanish taxa of Lithospermum L. sensu lato (Lithospermum sensu stricto, Neatostema, Buglossoides and Lithodora), with the exception of Buglossoides gartonii (Bentham) I. M. Johnston, have been studied karyologically. The karyological characters allow the separation of three groups which do not correspond exactly with the morphological limits of the four genera actually recognized for Spain within Lithospermum sensu lato. Se estudian cariologicamente los taxones espanoles de Lithospermum L. sensu lato (Lithospennum sensu stricto, Neatostema, Buglossoides y Lithodora), salvo Buglossoides gastonii (Bentham) I. M. Johnston. Por los caracteres cariologicos se pueden separar tres grupos cuyos limites no coinciden exactamente con los de los cuatro generos actualrnente reconocidos para Espana dentro de Lithospcnum sensu lato.