1. the posterior part of the alimentary canal in arthropods and some other invertebrates, derived from an inward fold of the body wall
Usage: biology; anatomy

Examples

• The proctodaeum forms the final section of the insect’s digestive system.
• In arthropods, the proctodaeum is lined with cuticle like the external body surface.
• The proctodaeum connects the midgut to the anus in many invertebrates.
• During development, the proctodaeum invaginates from the posterior end of the embryo.
• The structure of the proctodaeum varies among different arthropod species.