Novas espécies de Acrosternum subgênero Chinavia (Heteroptera, Pentatomidae, Pentatomini)

Four new species of Acrosternum from Brazil are described: Acrosternum (Chinavia)immaculatum(Pará, Mato Grosso, Minas Gerais), A.(C.) panizzii (Paraná), A. (C.) pontagrossensis(Paraná)and A. (C.) rideri (Amazonas, Mato Grosso, Goiás, Distrito Federal, Minas Gerais). The external and internal genitalia of both sexes, except of A. (C.) pontagrossensis are studied. A key for the identification of all known species of the genus is included.