Unusual Phase Relationships Between The Forewings And Hindwings In Flying Dragonflies

Flying insects can generally be divided into two groups: ‘primitive’ orders with forewings and hindwings that move independently (for example, Odonata, Orthoptera, Isoptera) and more ‘advanced’ orders with wings that are functionally one pair, with the fore- and hindwings in contact so as to function as one wing (for example, Hymenoptera, Lepidoptera, Homoptera), or with only one pair of wings that functions primarily as a lifting surface (for example, Diptera, Strepsiptera).