Cassida vibex is a species of Tortoise beetle, distrubuted throughout Europe and Asia. They feed on plants, preferring those of the Asteraceae family. Cassida vibex, like many other Cassidinae species, exhibits colour polymorphism, normally ranging from bright green to dull brown.
The shell of Cassida vibex exhibits a slight metallic sheen. This is a caused by a combination of reflection of light from the minute semitransparent layers in the cuticle, and the presence of fluid between these layers.
The Cassidinae subfamily takes its common name, 'Tortoise Beetle' from the way some species (including Cassida vibex) look similar to a tortoise (other than the antennae).