RESUMO
BACKGROUND AND AIMS: Fifty-two populations were sampled in order to establish the taxonomic delimitation and relationships of eight taxa belonging to the A. majus L. and A. siculum Miller groups. METHODS: Data on 13 allozyme loci were recorded after extraction of fresh leaves and electrophoresis on horizontal 10% starch gels. KEY RESULTS: Genetic distances between conspecific populations are lower than for other species of the genus. CONCLUSIONS: These results support the recognition of A. majus, A. tortuosum, A. linkianum, A. cirrigherum, A. litigiosum and A. barrelieri at specific rank. The genetic distances, together with the lack of morphological differences and the sympatric distribution ranges, support the inclusion of A. australe into A. tortuosum, A. dielsianum into A. siculum, and A. latifolium subsp. intermedium as a synonym of A. latifolium. The results support separation of the taxa studied into two groups, coinciding with series Sicula Rothm. and Majora, but disagreeing with the arrangement of species into them. According to our results, Sicula consist of A. siculum and Majora consists of A. latifolium, A. majus, A. tortuosum, A. linkianum, A. cirrigherum, A. litigiosum and A. barrelieri.
