He was suffect consul in the nundinium of March-June 79 as the colleague of Lucius Junius Caesennius Paetus.
However, the existence of a Publius Calvisius Ruso Julius Frontinus, attested by an inscription found in Pisidian Antioch, complicates matters.
This was the accepted consensus until the 1980s when Eric Birley published a paper wherein he voiced doubts he had for 25 years with this identification.
[4] Syme also proposed that the older son, Calvisius Ruso, had married a Dasumia, basing his reasoning on the fragmentary text of the Testamentum Dasumii; however, subsequent research and discoveries have weakened the possibility of a connection between the individuals mentioned in that inscription and Calvisius Ruso.
[5] Based on the lack of evidence for these personages, one cannot easily decide which conclusion is closest to the truth.