elytra

Elytra are the hardened forewings of beetles (order Coleoptera). They consist of the first pair of wings, modified into protective covers that shield the hind wings and the abdomen when the insect is at rest. The elytra arise from the thoracic dorsal plates and are typically rigid and chitinous. They meet along the midline of the back and are hinged to the mesothorax, allowing them to be raised or kept closed.

In most beetles, elytra are opaque and often embossed or grooved; they lack the venation of membranous wings. Colors and patterns vary widely and may serve camouflage, mimicry, or warning.

For flight, the beetle raises the elytra and extends the membranous hind wings beneath; the hind wings are unfolded and then folded again after flight. In many species, the elytra do not participate in flight. In some lineages, the elytra are fused and hind wings are reduced or absent, making the beetle flightless.

Elytra are a defining feature of beetles; the singular form is elytron. They are an important taxonomic character in identification and classification, with variation in sculpture, color, and striations used to differentiate genera and species.