Elytron

The elytra of this cockchafer are readily distinguished from the transparent hindwings.

An elytron (from [ἔλυτρον] Error: {{Lang-xx}}: text has italic markup (help) "sheath"; plural: elytra) is a modified, hardened forewing of certain insect orders, notably beetles (Coleoptera) and true bugs (Hemiptera). An elytron is sometimes also referred to as a shard.

The elytra primarily serve as protection for the hindwings underneath, which are used for flying. To fly, the insect opens the elytra and then extends the hindwings, flying while still holding the elytra open.

In some groups, the elytra are fused together, rendering the insect flightless. Some of the ground beetles (family Carabidae) are a good example of this.

The term is also used to describe the hard scales of some polychaete worms, notably the Polynoidae. These outgrowths of the body wall are distinguished from chaeta, which grow from follicles and thus possess roots.