||Abstract AIM OF THE STUDY: Written records of oral medical traditions have had significant impact on the development of medicine and the pharmacopoeias. Modern ethnobotanical studies in Europe and the Mediterranean region, however, have so far largely overlooked the richness and accuracy of historic sources and ignored their probable influence on the development of today's local traditional medicines. Here, we explore the common fundament of traditional knowledge for the medicinal plant uses in Sardinia and Sicily by comparing the selection of medicinal species and specific uses with those of Dioscorides' De Materia Medica. MATERIALS AND METHODS: We use (i) a quantification of citations for medicinal species mentioned in ethnobotanical studies conducted in Sardinia and Sicily (ii) a comparison of the flora and medicinal flora with a chi(2)-test (iii) a binomial approach recently introduced into ethnobotany (iv) a comparison of the most frequently used species with the indications cited in Dioscorides' De Materia Medica (v) and a crosscheck of all mentioned species with their appearance in Berendes' translation of De Materia Medica. RESULTS: We identified a core group of 170 medicinal species used on either islands, which accumulate 74% of all citations and are best represented in De Materia Medica. The 15 most frequently used species of both islands demonstrate intriguing parallels for indications with Dioscorides' work. CONCLUSION: The ethnopharmacopoeia of Sicily and Sardinia are shallow stereotypes of the different editions of De Materia Medica and talking of oral tradition in this respect is a contradiction. The medicinal species of Sardinia and Sicily are largely widespread and common species, including many weeds, which are not facing threat of extinction. Therefore, using traditional medicinal practices as an argument for conservation biology or vice versa is not scientifically sound.