Changes in uropod setae during molting of the freshwater crayfish, Procambarus clarkii (Cambaridae) from the River Nile, Egypt

Molting cycle is an essential process for crustacean growth, associated with several changes, so this study was carried out to investigate how telson setae and uropods are changing during different molt stages and substages of crayfish Procambarus clarkii. Microscopically, distinct changes in morphological structure and color pattern of the examined setae from different molting stages especially preecdysis (premolt sub stages) and post ecdysis (A-B) were exhibited. Bases of uropod setae, setal lumens, setal matrices, and setal cones showed remarkable changes during molting cycle from substages D1 (early premolt) to stage B (post ecdysis), with distinct variations in epidermal retraction, pigmentation and setal development.