Abstract
The phytoseiid mite Macrocaudus multisetatus n. g., n. sp., is described from Brazil based on specimens collected on Salvinia sp. (Salviniaceae). This mite is unique in the following characteristics at different taxonomic levels: larvae with seta Z4 not considerably longer than most dorsal setae, nymphs and adults with J3 present, J5 unusually long and subequal to Z5, males with all 8 caudoventral setae in addition to paraanal and postanal setae (Phytoseiidae); both sexes with seta JV3 present and on the ventrianal shield (Amblyseiinae).