The Aculeus functioned as a Mandator III-class dreadnought within the Galactic Empire's and later the Dark Empire's navy. This starship was among the five Mandator III-class dreadnoughts that participated in the Dark Empire's offensive against the New Republic's hold on the Core Worlds during 10 ABY. Despite initial Imperial gains, internal strife erupted as the Imperial Mutiny saw various Imperial groups turning against each other. During this conflict, also taking place in 10 ABY, the Aculeus met its end, destroyed in combat against TIE/D automated starfighter squadrons above the planet of Drearia.
Jason Fry and Paul R. Urquhart mentioned the Aculeus in their 2012 reference book, The Essential Guide to Warfare.