Foraging for food, searching for mates, escape from predators or fly swatters, avoiding harsh or unfavorable conditions, and locating egg-laying sites are just a few points of insect biology intimately connected to flight behavior. We first consider structures of insect flight muscles. In tubular muscles, fibrils are arranged radially about a column of sarcoplasm that contains several nuclei. Mitochondria are interspersed in the radial area of the muscle. Dragonflies feature this type of flight muscle structure.
Tubular muscles occur in the legs of most insect species.
In close-packed muscles large mitochondria are dispersed between the cylindrical fibrils, which are about 1.5 to 2.0 m in diameter. Fibrillar muscles are characteristic of Hymenoptera, Diptera, Coleoptera and true bugs. Even though different phylogenic groups have developed various structural types of flight muscles, there are major similarities among them. All the muscle types have fibers as their physiological units because the fibers are bounded by a continuous sarcolemma or muscle cell membrane with the basement membrane attached. There are descriptions of fibers composed of several cells, however, a fiber is more correctly a single multinucleated cell, or syncitium.