Diversity of insect pollinators in the Iberian Peninsula

Numerous observations and studies that have been carried out in recent decades show that, in addition to bees ((Hymenoptera; Anthophila), other groups of insects play a major role in entomophilous pollination. This article reviews the information and literature available on the contribution of the main groups of pollinators that traditionally have been considered as "secondary": beetles, butterflies and moths, dipterans, wasps and ants. For each of these groups a common outline is followed, with a brief introduction, a summary of the basic characteristics - both morphological and behavioral - in relation to pollination, their effectiveness as pollinators and their conservation status in the Iberian Peninsula. This review highlights the importance of all these groups in entomophilous pollination and the need to include them in comprehensive studies on this phenomenon. Although data are generally very limited, there is clear evidence of a general decline in most of these groups which calls for a pressing need to improve knowledge about their population trends.