Effective period / Period of releases: 1971 - 1978

Members: Júlio Pereira, Pedro Wallenstein, Pedro Castro, João Seixas, Rui Reis, Urbano Oliveira, Luís Filipe Castro, José Castro (2)

The initial Petrus Castrus in 1971: Pedro Castro: vocals, guitar and bass; José Castro: keyboards, synthesizer and vocals; Júlio Pereira: guitar; Rui Reis: organ; João Seixas: drums. Júlio Pereira left the band shortly after the recording of Mestre. The band suspended activity in 1974 and Rui Reis and João Seixas left to form the band Plutónicos, and the hard/ heavy band A Ferro E Fogo (later known as Ferro & Fogo, "Iron & Fire"). In 1976, the Castro brothers returned with a new lineup: Pedro Castro: vocals, guitar and bass; José Castro: keyboards, synthesizer and vocal; Urbano Oliveira: drums. Two years later, their album Ascenção e Queda was made with contributions from: Fernando Girão: guitar; Rui Serrão: bass; Lena D'Água: vocais; Nuno Rodrigues: vocals.