Abstract
The taxonomy and morphological diversity of the endemic South American cicadellid genus Agudus Oman are reviewed. Two new synonymies are proposed: A. amabilis Linnavuori & DeLong, 1978 equals A. blockeri Cheng, 1980, syn. nov.; A. typicus Oman, 1938 equals A. cyrtobrachium Cheng, 1980, syn. nov. Six new species are described and illustrated: A. clavistylus, A. cordifer, A. ellipticus, A. inesae, A. tenuistylus, and A. uncifer spp. nov. Previously described species of Agudus have the wings fully developed, or nearly so, but three of the new species have strongly reduced wings in both males and females and were only collected by vacuuming in pampas grasslands of northern Argentina. A key for identification of males of all 16 known species of the genus is provided.
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