The females and nests are described of two new species of social wasps (Hymenoptera, Vespidae) from dry evergreen forest on the Ilha de Maraca, Roraima, Brazil. Mischocyttarus (Monocyttarus) maracaensis sp.n. closely resembles M. flavicornis Zikan, 1935 in morphology and coloration. Polybia (Myrapetra) roraimae sp.n. is a member of the P. occidenlalis (Olivier, 1791) group of species.
Hymenoptera; Vespidae; Mischocyttarus; Polybia; Amazônia; Brazil; systematics