Postmolt is the stage just following exuviation (shedding of the old exoskeleton). It is the period when the exoskeleton expands due to increased hemolymph volume from water influx. Water influx occurs across the epidermis, gills, and gut. After several hours or days (depending upon total length of the molt cycle), the new exoskeleton hardens and retains its rigidity (Chang, 1992).
Immediately after ecdysis, the only layers present are the epicuticle and exocuticle. Within a few hours the epidermis starts to secrete the endocuticle. Most of the cuticle must be derived from materials stored in the epidermis, as feeding does not begin until the prawn is well into the intermolt stage. This secretion continues until the prawns are in the intermoult condition, when the three layers are fully formed (Dall et al., 1990).
