was a captain of gladiators in Otho's army, A. D. 69. Ascending the stream of the Po with a detachment of the Ravenna fleet, Macer drove the Vitellians from the left bank of the river, but shortly before the final defeat of his party at Bedriacum was himself repulsed, and displaced by Otho from his command. Macer's name was erased by Vitellius from the list of supplementary consuls for A. D. 69. (Tac. Hist. 2.23, 35, 36, 71.) Plutarch (Plut. Oth. 10) mentions Otho's gladiators, but not the name of their leader.
[W.B.D]A Dictionary of Greek and Roman biography and mythology
Smith, William
A Dictionary of Greek and Roman biography and mythology. William Smith, LLD, ed. 1890