Malacostracan crustaceans of the fossil order Pygocephalomorpha are conspicuous elements in brackish to freshwater faunas in the upper Carboniferous of Laurentia and lower Permian of Gondwana. A pronounced sexual dimorphism is recognizable within its members, with Pygocephalomorpha females bearing o€ ostegites: modified epipodites that hold a brood pouch where the eggs develop until juvenile stage, with no planktonic dispersal of larvae. The preservation of o€ ostegites is quite rare and is described here for the first time from the American continents. The specimens, ventrally preserved Liocaris huenei females bearing o€ ostegites, come from the Irati Formation, a lower Permian sequence of the Paran a Basin, from an outcrop in southern Brazil. The o€ ostegites are similar to those previously described for Pygocephalomorpha, displaying seven pairs of overlapping epipodites that cover the whole cephalothorax.