Moult cycle staging in decapod crustaceans (Pleocyemata) and the Australian crayfish, Cherax destructor Clark, 1936 (Decapoda, Parastacidae)
Sarsha Gorissen, D. C. Sandeman
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 (D 0 ), 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.