Marcus Aquilius Regulus was a Roman senator, and notorious delator or informer who was active during the reigns of Nero and Domitian.
Regulus is one of the best known examples of this occupation, in the words of Steven Rutledge, due to "the vivid portrait we have of his life and career in Pliny, Tacitus, and Martial.
Rutledge points to the judgment of Martianus Capella, who ranked him with Pliny the Younger and Fronto as the greatest Roman orators after Cicero.
[3] Paul von Rohden suggests his father might be identified with Lucius Aquillius L.f. Regulus, the pontifex and quaestor of Tiberius mentioned in CIL VI, 2122.
His period of greatest notoriety was during the reign of Nero, when Regulus prosecuted Marcus Licinius Crassus Frugi, Servius Cornelius Scipio Salvidienus Orfitus, and was involved in the cases of Quintus Sulpicius Camerinus Peticus and his son.