A remarkable new species group of green seed beetles from genus Amblycerus Thunberg (Coleoptera, Chrysomelidae, Bruchinae), with description of a new Brazilian species.

Chrysomelidae) are usually small and inconspicuous, with only a few species drawing the attention. Here we deal with several unusually colored species of Amblycerus Thunberg, 1815, one of the two most diverse bruchine genera in the Western hemisphere. We define the virens group that consists of five species whose bodies are covered with a green vestiture, including one new for science, Amblycerus medialis Ribeiro-Costa, Vieira & Manfio, sp. n. (Type locality: Brazil: Pará, Rondônia). This study also provides redescriptions, diagnoses, comparative notes, illustrations, geographic distribution records and a key to the species in this group.