A further novel species of Macrobrachium from Brazil (Decapoda, Palaemonidae), lacking a mandibular palp

A new species of Macrobrachium from the Paraguay River basin, Brazil, is described. The new species is distinguished from most of its congeners by the absence of a mandibular palp. Morphologically, the new species is similar to M. bouvieri (Sollaud, 1911), with the presence of a postorbital rostral tooth, a straight rostrum, and the presence of a double row of setae without gaps over the teeth along the ventral margin of rostrum, separating it from that species, as well as the other eight species of Macrobrachium lacking a mandibular palp.