<Li> Cubitus anterior (CuA) </Li> <Li> Anal veins (AA, AP)--veins behind the cubitus, separated by anal fold . </Li> <P> In most species of beetles, the front pair of wings are modified and sclerotised (hardened) to form elytra and they protect the delicate hindwings which are folded beneath . The elytra are connected to the pterathorax; being called as such because it is where the wings are connected (pteron meaning "wing" in Greek). The elytra are not used for flight, but tend to cover the hind part of the body and protect the second pair of wings (alae). The elytra must be raised in order to move the hind flight wings . A beetle's flight wings are crossed with veins and are folded after landing, often along these veins, and are stored below the elytra . In some beetles, the ability to fly has been lost . These include some ground beetles (family Carabidae) and some "true weevils" (family Curculionidae), but also some desert and cave - dwelling species of other families . Many of these species have the two elytra fused together, forming a solid shield over the abdomen . In a few families, both the ability to fly and the elytra have been lost, with the best known example being the glow - worms of the family Phengodidae, in which the females are larviform throughout their lives . </P> <P> The two pairs of wings are found on the middle and third segment, or mesothorax and metathorax respectively . In the more recent genera, the wings of the second segment are much more pronounced, however some more primitive forms have similarly sized wings of both segments . The wings are covered in scales arranged like shingles, forming the extraordinary variety seen in color . The mesothorax is evolved to have more powerful muscles to propel moth or butterfly through the air, with the wing of said segment having a stronger vein structure . The largest superfamily, Noctuidae, has the wings modified to act as Tympanal or hearing organs Modifications in the wing's venation include: </P>

Where are the elytra located if they are present on an insect