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#2: Beetle Elytra




Litinsects #2: Beetle Elytra

Beetles, like this ladybug here, come in all shapes and sizes but have one basic thing in common: hardened (sclerotized) forewings, named ELYTRA, which cover and protect their bodies. In flight, the elytra are lifted up and the hindwings are extended so, functionally, beetles actually only use one pair of wings to fly.

Now for some FACTS about beetle wings...🐞
  • The scientific name for beetles is COLEOPTERA, which comes from the Greek koleos, meaning sheath, and pteron, meaning wing
  • Elytra are not “used in flight” per se but do have an effect on lift and drag. They also serve to TRAP MOISTURE and keep the hindwings from dehydrating
  • Beetles’ hindwings are usually much longer than their elytra. At rest, they are FOLDED longitudinally (the long way) and then transversely (across) and tucked under the elytra (see second picture)
  • Most insects fly with their legs tucked against their bodies to reduce drag but beetles fly with outstretched legs (kind of like a Superman pose). A recent study found that beetles actually use their legs to help make fast maneuvers during flight
  • Some species of beetles have lost the ability to fly, in which case their elytra have FUSED together to form a solid shield over their abdomen
  • Remember when I said “all beetles have elytra”? Well there’s aaaalways an exception... in this case they are called glow worms. These families of beetles are bioluminescent and have adult LARVIFORM females, meaning the adult stage looks very much like the wingless larval stage
Next time you see a beetle flying, see if you can spot its lifted elytra or, once it’s landed, watch as it folds and tucks its wings back underneath!
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