CSS Ivy was a sidewheel steamer and privateer purchased by Commodore Lawrence Rousseau for service with the Confederate States Navy, and chosen by Commodore George Hollins for his Mosquito Fleet. The Mosquito Fleet was a group of riverboats converted to gunboats, and used to defend the Mississippi River in the area of New Orleans during the American Civil War.
Equipped with a powerful rifled 32-pounder, Ivy fought with the Mosquito Fleet at the Confederate victory of the Battle of the Head of Passes and their defeat at the Battle of Island Number 10. Subsequently, trapped in the Yazoo River, Ivy was destroyed to prevent her capture by the Union in May 1863.