son of the emperor Decius, upon whose accession in A. D. 249 he received the appellations of Caesar
and Princeps Jueentuttis.
In 2.51 he was consul, was admitted to a participation in the title of Augustus, and towards the close of the year was slain along with his father in a bloody battle fought against the Goths in Thrace. [DECIUS.] We gather from coins that his designation at full length was Q. Herennius Etruscus Messius Trajanus Decius,
the names Herennius Etruscus
being derived from his mother Herennia Etruscilla, while the rest were inherited from his sire. (Aurel. Vict. de Caes.
xxix.; Zonar. 12.20