A new species of Echium (Boraginaceae) from the island of Porto Santo (Madeira Archipelago)

A new species endemic from the island of Porto Santo (Madeira Archipelago) is described as Echium portosanctensis J.A. Carvalho, Pontes, Batista-Marques & R. Jardim. Morphological studies based on reproductive and vegetative traits revealed a set of diagnostic characters confirming separation of E. portosanctensis from other recognized species at sectional level. A taxonomic diagnosis, a morphological description and illustrations of the new species are provided. Images, distribution maps, ecological data and a key for Madeiran species of Echium are also provided. Diagnostic characters, conservation status, threats and speciation mechanisms are discussed. In addition, reports on the occurrence of E. candicans on the island of Porto Santo are also discussed.