He was later elected to a suffect consul in 217 BC, in place of Gaius Flaminius, who had been killed at the Battle of Lake Trasimene.
[4] However, Polybius reports that Regulus and his consular colleague of 217 BC, Gnaeus Servilius Geminus, were killed as part of the army defeated at Cannae.
[6][7] During his censorship, he was strict towards those who attempted to evade military service after Cannae and those who had broken oaths to rejoin the Romans after being captured by Hannibal.
However, Regulus was compelled to step down before completing the lustrum when his colleague, Publius Furius Philus, died unexpectedly.
[10] In notes, Broughton further explains that the textual tradition is unclear: this Atilius may in fact be an Aemilius and others have suggested Serranus as cognomen rather than Regulus.