Order Odonata comprise the Dragonflies (suborder anisotera) and
damselflies (suborder zygoptera), and like cockroaches is one
of the oldest types of insects. They appeared in the Devonian
during the Paleozoic,
a time when their distant cousins, the trilobites, were still
abundant. This ancient, fixed-wing design apparently is a good
one, given that there are some 5500 extant species known of Odonata.