Moult cycle staging in decapod crustaceans (Pleocyemata) and the Australian crayfish, Cherax destructor Clark, 1936 (Decapoda, Parastacidae)

Abstract

Abstract We tabulated decades of published moult stage criteria of Decapoda: Pleocyemata on setogenesis and changes in pleopods, uropods and gastroliths; and reviewed them focusing on the comparative biology of Cherax destructor. We found their staging criteria relatively consistent. For C. destructor, lacking were a comprehensive description with micrographs; a juvenile application; and, known stage duration. Therefore, we developed comprehensive moult staging techniques in juvenile C. destructor using pleopods, antennules and gastroliths. Using pleopod staging, we found C. destructor exhibits anecdysis as a true transition stage (D0), which occupied around half the moult cycle. We successfully applied this method to juvenile and adult marbled crayfish. We report on these suggested novel techniques: moult staging using pleopods: novel in crayfish; moult staging using antennules: novel in decapods; moult staging using gastrolith deposition: novel in C. destructor; and, calculating the gastrolith moult mineralization index using height: novel in decapods.