Hitherto Aeonium (sect. Leuconium) urbicum has been considered endemic to the islands of Tenerife and La Gomera (Canary Islands). A close morphological examination of the populations on both islands revealed clear differences in taxonomically significant features. These findings justify the recognition of the populations in S Tenerife as a new variety, A. urbicum var. meridionale, and the segregation of the populations on La Gomera as a new species, A. appendiculatum. The new taxa are described and illustrated, their relationships are discussed and a key to the single-stemmed taxa of A. sect. Leuconium is provided.
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