There are many reasons why stomatopods lose their raptorial appendages; physical damage, toxins, poor water quality, weak when molting due to disease, parasites or poor living conditions, etc. It is often difficult to trace the cause, but heat, cold, low oxygen, major rapid salinity change, and a variety of chemicals ranging from cleaning products to tobacco smoke can all damage the muscles of the raptorial appendage causing the propodus to be permanently extended. Some species are more prone to appendage loss than others. O. scyllarus and Lysiosquillina are particularly vulnerable.
When the raptorial appendages are permanently extended, the animal usually tears off the damage appendage(s) and attempts to regenerate them. This usually takes three molts before they are functional and fourt to get back to near normal size. When only one appendage is lost, the molt is not accelerated. However, when both appendages are damaged, the animal usually resorbs its ovaries or testes and mobilizes all resources into rapidly molting. This can speed up the process 50% if the animal has lots to eat. Be sure to include lots of calcium in the diet. Krill, shrimp cuticle, etc. will help. Most stomatopods have very powerful mandibles and can cut up crustacean cuticle even when they can't strike.
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