A new genus and species, Argentinovertex coineaui gen. nov., sp. nov., collected on Prosopis flexuosa litter (Mesquite) in the Monte phytogeographic Province, Argentine Republic, is described from adult males and females, and the tritonymph; some schematic drawings and scanning electron micrographs give further information. The new genus Argentinovertex shows noticeable differences to the other genera of the family Scutovertecidae, especially: type of cerotegument; rostral hood shape; lack of setae in; notogastral shape and number of notogastral setae; lateral structure of body; leg shape, distribution and shape of leg setae; prodorsum shape, distribution and shape of gastronotal setae in tritonymph.