The Insect-class gunboats (or large China gunboats) were a class of small, but well-armed Royal Navy ships designed for use in shallow rivers or inshore. They were intended for use on the Danube against Austria-Hungary (the China name was to disguise their function). The first four ships—Gnat, Mantis, Moth and Tarantula—were first employed during the Mesopotamian Campaign of the First World War on the Euphrates and Tigris rivers.