Ventilatory movements of the abdomen and branchial apparatus in dragonfly larvae (Odonata: Anisoptera)



Use of cine-photography in the analysis of ventilatory movements has necessitated a reappraisal of the ventilatory patterns previously described in dragonfly larvae. Movements of the abdominal exoskeleton, monitored by cine-photography, phototransistor and strain gauge, are discussed in relation to known muscular activity. Internal movements of the branchial apparatus, which consists of two chambers and three valves, are also illustrated in the intact animal. The mechanism of “gulping” ventilation (Va) in dragonfly larvae is discussed.