3.26g
Obv: Radiate bust of Gallienus right "GALLIENVS AVG"
Rev: "NEPTVNO CONS AVG" Hippocamp right "N" in exergue
This type calls for the protection of Neptune in the revolt of Aureolus. It didn't work as he was murdered by his own troops.
RSC 667, RIC 245, RCV 10292