Floral biology of the Canarian Echium wildpretii: bird-flower or a water resource to desert bees?

The red corolla colour, the relatively large volume of nectar and the low concentration of sucrose in the nectar of Echium wildpretii are traits related to bird pollination, while its ultraviolet colour and floral morphology may attract bees. It is suggested that the species may serve as a water resource to solitary desert bees in nature.